Add revision dropdown, editable WO#, and fix Revised proposal approval

- Fix: ApproveAsync now accepts both InReview and Revised proposals
- Revision dropdown in header: navigate between revisions, download PDF per rev
- Work Order Number editable in admin workspace (same pattern as PO#)
- Added WorkOrderNumber to UpdateProposalRequest DTO and service
- Info bar reordered: Customer, Site, WO#, PO#, Category, Priority
- Uniform font sizing across info bar (0.75rem labels, 0.875rem values)
- Typed getHistory API to return ProposalDetail[]
- Download PDF button in action bar for Sent/Revised proposals

api/src/ProposalSystem.Application/DTOs/ProposalDtos.cs

@@ -4,6 +4,7 @@ namespace ProposalSystem.Application.DTOs;
 
 public record CreateProposalRequest(
     string WorkOrderNumber,
+    string? PoNumber,
     string CustomerName,
     string CustomerAddress,
     string ScopeOfWork,
@@ -15,6 +16,8 @@ public record CreateProposalRequest(
 public record UpdateProposalRequest(
     string? RefinedScope,
     string? Notes,
+    string? PoNumber,
+    string? WorkOrderNumber,
     Guid? AssignedAdminId,
     ProposalStatus? Status
 );
@@ -23,6 +26,7 @@ public record ProposalResponse(
     Guid Id,
     string ProposalNumber,
     string WorkOrderNumber,
+    string? PoNumber,
     string CustomerName,
     string CustomerAddress,
     string ScopeOfWork,

api/src/ProposalSystem.Infrastructure/Services/ProposalService.cs

@@ -40,6 +40,7 @@ public class ProposalService : IProposalService
             Id = Guid.NewGuid(),
             ProposalNumber = proposalNumber,
             WorkOrderNumber = request.WorkOrderNumber,
+            PoNumber = request.PoNumber,
             CustomerName = request.CustomerName,
             CustomerAddress = request.CustomerAddress,
             ScopeOfWork = request.ScopeOfWork,
@@ -165,6 +166,12 @@ public class ProposalService : IProposalService
         if (request.Notes != null)
             proposal.Notes = request.Notes;
 
+        if (request.PoNumber != null)
+            proposal.PoNumber = request.PoNumber;
+
+        if (request.WorkOrderNumber != null)
+            proposal.WorkOrderNumber = request.WorkOrderNumber;
+
         if (request.AssignedAdminId.HasValue)
             proposal.AssignedAdminId = request.AssignedAdminId.Value;
 
@@ -192,7 +199,7 @@ public class ProposalService : IProposalService
         if (proposal.Status == ProposalStatus.Approved)
             return MapToResponse(proposal);
 
-        if (proposal.Status != ProposalStatus.InReview)
+        if (proposal.Status != ProposalStatus.InReview && proposal.Status != ProposalStatus.Revised)
             throw new InvalidOperationException("Only proposals in review can be approved");
 
         if (!proposal.LineItems.Any() || proposal.LineItems.All(li => li.TotalPrice <= 0))
@@ -210,6 +217,31 @@ public class ProposalService : IProposalService
         return MapToResponse(proposal);
     }
 
+    public async Task<ProposalResponse> ReturnToReviewAsync(Guid id, CancellationToken ct = default)
+    {
+        var proposal = await _db.Proposals
+            .Include(p => p.SubmittedBy)
+            .Include(p => p.ApprovedBy)
+            .FirstOrDefaultAsync(p => p.Id == id, ct)
+            ?? throw new KeyNotFoundException($"Proposal {id} not found");
+
+        if (proposal.Status == ProposalStatus.InReview)
+            return MapToResponse(proposal);
+
+        if (proposal.Status != ProposalStatus.Approved)
+            throw new InvalidOperationException("Only approved proposals can be returned to review");
+
+        proposal.Status = ProposalStatus.InReview;
+        proposal.ApprovedById = null;
+        proposal.ApprovedAt = null;
+        proposal.UpdatedAt = DateTime.UtcNow;
+
+        await _db.SaveChangesAsync(ct);
+        await _audit.LogAsync(AuditAction.ReturnToReview, id, null, ct);
+
+        return MapToResponse(proposal);
+    }
+
     public async Task<ProposalResponse> MarkSentAsync(Guid id, CancellationToken ct = default)
     {
         var proposal = await _db.Proposals
@@ -259,6 +291,7 @@ public class ProposalService : IProposalService
             Id = Guid.NewGuid(),
             ProposalNumber = $"{proposal.ProposalNumber}-R{proposal.CurrentRevision + 1}",
             WorkOrderNumber = proposal.WorkOrderNumber,
+            PoNumber = proposal.PoNumber,
             CustomerName = proposal.CustomerName,
             CustomerAddress = proposal.CustomerAddress,
             ScopeOfWork = proposal.ScopeOfWork,
@@ -366,6 +399,7 @@ public class ProposalService : IProposalService
         p.Id,
         p.ProposalNumber,
         p.WorkOrderNumber,
+        p.PoNumber,
         p.CustomerName,
         p.CustomerAddress,
         p.ScopeOfWork,

web/src/lib/api/admin.ts

@@ -1,4 +1,5 @@
 import apiClient from './client';
+import { type ProposalDetail } from './proposals';
 
 export interface DashboardStats {
   pendingCount: number;
@@ -10,6 +11,8 @@ export interface DashboardStats {
 export interface UpdateProposalRequest {
   refinedScope?: string;
   notes?: string;
+  poNumber?: string;
+  workOrderNumber?: string;
   assignedAdminId?: string;
 }
 
@@ -38,6 +41,10 @@ export const adminApi = {
     await apiClient.post(`/proposals/${id}/approve`);
   },
 
+  returnToReview: async (id: string): Promise<void> => {
+    await apiClient.post(`/proposals/${id}/return-to-review`);
+  },
+
   sendProposal: async (id: string): Promise<void> => {
     await apiClient.post(`/proposals/${id}/send`);
   },
@@ -46,7 +53,7 @@ export const adminApi = {
     await apiClient.post(`/proposals/${id}/revise`);
   },
 
-  getHistory: async (id: string): Promise<unknown[]> => {
+  getHistory: async (id: string): Promise<ProposalDetail[]> => {
     const res = await apiClient.get(`/proposals/${id}/history`);
     return res.data;
   },
@@ -65,9 +72,15 @@ export const adminApi = {
     return res.data;
   },
 
-  getPdf: async (id: string): Promise<{ downloadUrl: string; expiresAt: string } | null> => {
-    const res = await apiClient.get(`/proposals/${id}/pdf`);
+  getPdf: async (id: string, regenerate = false): Promise<{ downloadUrl: string } | null> => {
+    const params = regenerate ? '?regenerate=true' : '';
+    const res = await apiClient.get(`/proposals/${id}/pdf${params}`, {
+      responseType: 'blob',
+      validateStatus: (status) => status < 500,
+    });
     if (res.status === 202) return null;
-    return res.data;
+    const blob = res.data as Blob;
+    const downloadUrl = URL.createObjectURL(blob);
+    return { downloadUrl };
   },
 };

web/src/pages/admin/workspace/AdminWorkspace.tsx

@@ -1,5 +1,5 @@
-import { useState, useEffect, useCallback } from 'react';
-import { useParams, useNavigate, useBlocker } from 'react-router-dom';
+import { useState, useEffect, useRef } from 'react';
+import { useParams, useNavigate } from 'react-router-dom';
 import { useQuery, useMutation } from '@tanstack/react-query';
 import {
   Box,
@@ -17,6 +17,9 @@ import {
   DialogActions,
   CircularProgress,
   Alert,
+  Menu,
+  MenuItem,
+  IconButton,
 } from '@mui/material';
 import ArrowBackIcon from '@mui/icons-material/ArrowBack';
 import SaveIcon from '@mui/icons-material/Save';
@@ -25,16 +28,49 @@ import SendIcon from '@mui/icons-material/Send';
 import RefreshIcon from '@mui/icons-material/Refresh';
 import HistoryIcon from '@mui/icons-material/History';
 import PictureAsPdfIcon from '@mui/icons-material/PictureAsPdf';
+import DownloadIcon from '@mui/icons-material/Download';
+import ArrowDropDownIcon from '@mui/icons-material/ArrowDropDown';
+import UndoIcon from '@mui/icons-material/Undo';
 import { toast } from 'react-toastify';
 import { proposalsApi, type ProposalDetail } from '../../../lib/api/proposals';
 import { lineItemsApi, type LineItem } from '../../../lib/api/lineItems';
-import { adminApi } from '../../../lib/api/admin';
+import { adminApi, type AuditEntry } from '../../../lib/api/admin';
 import { queryClient } from '../../../lib/queryClient';
 import { QUERY_KEYS } from '../../../constants/queryKeys';
 import LineItemEditor, { type EditableLineItem } from '../../../components/admin/LineItemEditor';
 import VendorDataPanel from '../../../components/admin/VendorDataPanel';
 import SimilarProposalsPanel from '../../../components/admin/SimilarProposalsPanel';
-import { STATUS_COLORS } from '../../../constants';
+import { STATUS_COLORS, STATUS_LABELS, PRIORITY_LABELS } from '../../../constants';
+
+const ACTION_LABELS: Record<string, string> = {
+  Submit: 'Submitted',
+  Edit: 'Edited',
+  Approve: 'Approved',
+  ReturnToReview: 'Returned to Review',
+  MarkSent: 'Marked Sent',
+  CreateRevision: 'Revision Created',
+  EditLineItem: 'Line Items Updated',
+  EditScope: 'Scope Edited',
+  Regenerate: 'Regenerated',
+  GeneratePDF: 'PDF Generated',
+  Download: 'Downloaded',
+  AssignAdmin: 'Admin Assigned',
+  UpdateRole: 'Role Updated',
+  Revise: 'Revised',
+};
+
+function formatAction(action: string): string {
+  return ACTION_LABELS[action] || action.replace(/([A-Z])/g, ' $1').trim();
+}
+
+function formatDetails(details: string): string {
+  try {
+    const parsed = JSON.parse(details);
+    return parsed.message || details;
+  } catch {
+    return details;
+  }
+}
 
 export default function AdminWorkspace() {
   const { id } = useParams<{ id: string }>();
@@ -42,10 +78,15 @@ export default function AdminWorkspace() {
 
   const [lineItems, setLineItems] = useState<EditableLineItem[]>([]);
   const [refinedScope, setRefinedScope] = useState('');
+  const [workOrderNumber, setWorkOrderNumber] = useState('');
+  const [poNumber, setPoNumber] = useState('');
   const [approveDialogOpen, setApproveDialogOpen] = useState(false);
   const [sendDialogOpen, setSendDialogOpen] = useState(false);
   const [reviseDialogOpen, setReviseDialogOpen] = useState(false);
+  const [returnToReviewDialogOpen, setReturnToReviewDialogOpen] = useState(false);
   const [dirty, setDirty] = useState(false);
+  const [revMenuAnchor, setRevMenuAnchor] = useState<null | HTMLElement>(null);
+  const [downloadingRevId, setDownloadingRevId] = useState<string | null>(null);
 
   const { data: proposal, isLoading } = useQuery<ProposalDetail>({
     queryKey: [QUERY_KEYS.proposals, id],
@@ -59,6 +100,18 @@ export default function AdminWorkspace() {
     enabled: !!id,
   });
 
+  const { data: auditTrail } = useQuery<AuditEntry[]>({
+    queryKey: ['audit', id],
+    queryFn: () => adminApi.getAudit(id!),
+    enabled: !!id,
+  });
+
+  const { data: revisionHistory } = useQuery<ProposalDetail[]>({
+    queryKey: [QUERY_KEYS.proposals, id, 'history'],
+    queryFn: () => adminApi.getHistory(id!),
+    enabled: !!id,
+  });
+
   useEffect(() => {
     if (fetchedLineItems) {
       setLineItems(
@@ -80,9 +133,14 @@ export default function AdminWorkspace() {
   useEffect(() => {
     if (proposal) {
       setRefinedScope(proposal.refinedScope || proposal.scopeOfWork);
+      setWorkOrderNumber(proposal.workOrderNumber || '');
+      setPoNumber(proposal.poNumber || '');
     }
   }, [proposal]);
 
+  const dirtyRef = useRef(dirty);
+  dirtyRef.current = dirty;
+
   useEffect(() => {
     if (!dirty) return;
     const handler = (e: BeforeUnloadEvent) => {
@@ -92,17 +150,9 @@ export default function AdminWorkspace() {
     return () => window.removeEventListener('beforeunload', handler);
   }, [dirty]);
 
-  const blocker = useBlocker(
-    useCallback(
-      ({ currentLocation, nextLocation }: { currentLocation: { pathname: string }; nextLocation: { pathname: string } }) =>
-        dirty && currentLocation.pathname !== nextLocation.pathname,
-      [dirty],
-    ),
-  );
-
   const saveMutation = useMutation({
     mutationFn: async () => {
-      await adminApi.updateProposal(id!, { refinedScope });
+      await adminApi.updateProposal(id!, { refinedScope, workOrderNumber, poNumber });
       await lineItemsApi.bulkUpdate(
         id!,
         lineItems.map((li) => ({
@@ -121,6 +171,7 @@ export default function AdminWorkspace() {
     onSuccess: () => {
       queryClient.invalidateQueries({ queryKey: [QUERY_KEYS.proposalLineItems, id] });
       queryClient.invalidateQueries({ queryKey: [QUERY_KEYS.proposals, id] });
+      queryClient.invalidateQueries({ queryKey: ['audit', id] });
       setDirty(false);
       toast.success('Changes saved');
     },
@@ -136,6 +187,7 @@ export default function AdminWorkspace() {
     onSuccess: () => {
       queryClient.invalidateQueries({ queryKey: [QUERY_KEYS.proposals, id] });
       queryClient.invalidateQueries({ queryKey: [QUERY_KEYS.proposalLineItems, id] });
+      queryClient.invalidateQueries({ queryKey: ['audit', id] });
       setApproveDialogOpen(false);
       setDirty(false);
       toast.success('Proposal approved');
@@ -146,6 +198,7 @@ export default function AdminWorkspace() {
     mutationFn: () => adminApi.sendProposal(id!),
     onSuccess: () => {
       queryClient.invalidateQueries({ queryKey: [QUERY_KEYS.proposals, id] });
+      queryClient.invalidateQueries({ queryKey: ['audit', id] });
       setSendDialogOpen(false);
       toast.success('Proposal marked as sent');
     },
@@ -155,11 +208,22 @@ export default function AdminWorkspace() {
     mutationFn: () => adminApi.reviseProposal(id!),
     onSuccess: () => {
       queryClient.invalidateQueries({ queryKey: [QUERY_KEYS.proposals, id] });
+      queryClient.invalidateQueries({ queryKey: ['audit', id] });
       setReviseDialogOpen(false);
       toast.success('Revision created');
     },
   });
 
+  const returnToReviewMutation = useMutation({
+    mutationFn: () => adminApi.returnToReview(id!),
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: [QUERY_KEYS.proposals, id] });
+      queryClient.invalidateQueries({ queryKey: ['audit', id] });
+      setReturnToReviewDialogOpen(false);
+      toast.success('Proposal returned to review');
+    },
+  });
+
   const regenerateMutation = useMutation({
     mutationFn: () => adminApi.generateSuggestions(id!),
     onSuccess: () => {
@@ -168,11 +232,12 @@ export default function AdminWorkspace() {
   });
 
   const pdfMutation = useMutation({
-    mutationFn: () => adminApi.getPdf(id!),
+    mutationFn: (regenerate?: boolean) => adminApi.getPdf(id!, regenerate ?? false),
     onSuccess: (data) => {
       if (data?.downloadUrl) {
         window.open(data.downloadUrl, '_blank');
-        toast.success('PDF ready — downloading');
+        queryClient.invalidateQueries({ queryKey: ['audit', id] });
+        toast.success('PDF ready');
       } else {
         toast.info('PDF generation queued — try again in a few seconds');
       }
@@ -187,6 +252,29 @@ export default function AdminWorkspace() {
     setDirty(true);
   };
 
+  const DOWNLOADABLE_STATUSES = ['Approved', 'Sent', 'Revised'];
+
+  const handleDownloadPdf = async (revId: string, proposalNumber: string, revision: number) => {
+    setDownloadingRevId(revId);
+    try {
+      const result = await proposalsApi.getPdf(revId);
+      if (result) {
+        const a = document.createElement('a');
+        a.href = result.downloadUrl;
+        a.download = `${proposalNumber}-rev${revision}.pdf`;
+        a.click();
+        URL.revokeObjectURL(result.downloadUrl);
+        toast.success('PDF downloaded');
+      } else {
+        toast.info('PDF not yet generated for this revision');
+      }
+    } catch {
+      toast.error('Failed to download PDF');
+    } finally {
+      setDownloadingRevId(null);
+    }
+  };
+
   if (isLoading) {
     return (
       <Box sx={{ display: 'flex', justifyContent: 'center', py: 8 }}>
@@ -215,38 +303,116 @@ export default function AdminWorkspace() {
     <Box>
       {/* Header */}
       <Box sx={{ display: 'flex', alignItems: 'center', gap: 2, mb: 2 }}>
-        <Button startIcon={<ArrowBackIcon />} onClick={() => navigate('/admin')}>
+        <Button startIcon={<ArrowBackIcon />} onClick={() => {
+          if (dirty && !window.confirm('You have unsaved changes. Are you sure you want to leave?')) return;
+          navigate('/admin');
+        }}>
           Back
         </Button>
         <Typography variant="h5" sx={{ flexGrow: 1 }}>
           {proposal.proposalNumber}
         </Typography>
-        <Chip label={`Rev ${proposal.currentRevision}`} size="small" variant="outlined" />
-        <Chip label={proposal.status} color={STATUS_COLORS[proposal.status] || 'default'} />
+        <Chip
+          label={`Rev ${proposal.currentRevision}`}
+          size="small"
+          variant="outlined"
+          onClick={(e) => setRevMenuAnchor(e.currentTarget)}
+          onDelete={(e) => setRevMenuAnchor(e.currentTarget as HTMLElement)}
+          deleteIcon={<ArrowDropDownIcon />}
+          sx={{ cursor: 'pointer' }}
+        />
+        <Menu
+          anchorEl={revMenuAnchor}
+          open={Boolean(revMenuAnchor)}
+          onClose={() => setRevMenuAnchor(null)}
+        >
+          {(revisionHistory ?? [])
+            .sort((a, b) => a.currentRevision - b.currentRevision)
+            .map((rev) => (
+              <MenuItem
+                key={rev.id}
+                selected={rev.id === id}
+                dense
+                onClick={() => {
+                  setRevMenuAnchor(null);
+                  if (rev.id !== id) {
+                    if (dirty && !window.confirm('You have unsaved changes. Are you sure you want to switch revisions?')) return;
+                    navigate(`/admin/proposals/${rev.id}`);
+                  }
+                }}
+                sx={{ display: 'flex', justifyContent: 'space-between', gap: 2, minWidth: 160 }}
+              >
+                <Box>
+                  <Typography sx={{ fontSize: '0.8125rem', fontWeight: 600 }}>Rev {rev.currentRevision}</Typography>
+                  <Typography sx={{ fontSize: '0.75rem', color: 'text.secondary' }}>{STATUS_LABELS[rev.status] || rev.status}</Typography>
+                </Box>
+                {DOWNLOADABLE_STATUSES.includes(rev.status) && (
+                  <IconButton
+                    size="small"
+                    onClick={(e) => {
+                      e.stopPropagation();
+                      setRevMenuAnchor(null);
+                      handleDownloadPdf(rev.id, rev.proposalNumber, rev.currentRevision);
+                    }}
+                    disabled={downloadingRevId === rev.id}
+                  >
+                    <DownloadIcon sx={{ fontSize: '1rem' }} />
+                  </IconButton>
+                )}
+              </MenuItem>
+            ))}
+        </Menu>
+        <Chip label={STATUS_LABELS[proposal.status] || proposal.status} color={STATUS_COLORS[proposal.status] || 'default'} />
       </Box>
 
       {/* Proposal Info Bar */}
       <Card sx={{ mb: 2 }}>
-        <CardContent sx={{ py: 1.5, display: 'flex', gap: 3, flexWrap: 'wrap', alignItems: 'center' }}>
+        <CardContent sx={{ py: 1.5, display: 'flex', gap: 3, flexWrap: 'wrap', alignItems: 'flex-start' }}>
           <Box>
-            <Typography variant="caption" color="text.secondary">Customer</Typography>
-            <Typography variant="body2" sx={{ fontWeight: 600 }}>{proposal.customerName}</Typography>
+            <Typography sx={{ fontSize: '0.75rem', lineHeight: 1.5, color: 'text.secondary' }}>Customer</Typography>
+            <Typography sx={{ fontSize: '0.875rem', lineHeight: 1.5, fontWeight: 600 }}>{proposal.customerName}</Typography>
           </Box>
           <Box>
-            <Typography variant="caption" color="text.secondary">WO #</Typography>
-            <Typography variant="body2" sx={{ fontWeight: 600 }}>{proposal.workOrderNumber}</Typography>
+            <Typography sx={{ fontSize: '0.75rem', lineHeight: 1.5, color: 'text.secondary' }}>Site</Typography>
+            <Typography sx={{ fontSize: '0.875rem', lineHeight: 1.5, fontWeight: 600 }}>{proposal.customerAddress}</Typography>
           </Box>
           <Box>
-            <Typography variant="caption" color="text.secondary">Category</Typography>
-            <Typography variant="body2">{proposal.serviceCategory}</Typography>
+            <Typography sx={{ fontSize: '0.75rem', lineHeight: 1.5, color: 'text.secondary' }}>WO #</Typography>
+            {isEditable ? (
+              <TextField
+                size="small"
+                variant="standard"
+                placeholder="—"
+                value={workOrderNumber}
+                onChange={(e) => { setWorkOrderNumber(e.target.value); setDirty(true); }}
+                sx={{ width: 140, display: 'block', '& input': { fontSize: '0.875rem', lineHeight: 1.5, fontWeight: 600, p: 0 }, '& .MuiInput-root': { mt: 0 } }}
+              />
+            ) : (
+              <Typography sx={{ fontSize: '0.875rem', lineHeight: 1.5, fontWeight: 600 }}>{workOrderNumber || '—'}</Typography>
+            )}
           </Box>
           <Box>
-            <Typography variant="caption" color="text.secondary">Priority</Typography>
-            <Chip label={proposal.priority} size="small" sx={{ ml: 0.5 }} />
+            <Typography sx={{ fontSize: '0.75rem', lineHeight: 1.5, color: 'text.secondary' }}>PO #</Typography>
+            {isEditable ? (
+              <TextField
+                size="small"
+                variant="standard"
+                placeholder="—"
+                value={poNumber}
+                onChange={(e) => { setPoNumber(e.target.value); setDirty(true); }}
+                sx={{ width: 120, display: 'block', '& input': { fontSize: '0.875rem', lineHeight: 1.5, fontWeight: 600, p: 0 }, '& .MuiInput-root': { mt: 0 } }}
+              />
+            ) : (
+              <Typography sx={{ fontSize: '0.875rem', lineHeight: 1.5, fontWeight: 600 }}>{poNumber || '—'}</Typography>
+            )}
           </Box>
           <Box>
-            <Typography variant="caption" color="text.secondary">Address</Typography>
-            <Typography variant="body2">{proposal.customerAddress}</Typography>
+            <Typography sx={{ fontSize: '0.75rem', lineHeight: 1.5, color: 'text.secondary' }}>Category</Typography>
+            <Typography sx={{ fontSize: '0.875rem', lineHeight: 1.5, fontWeight: 600 }}>{proposal.serviceCategory}</Typography>
+          </Box>
+          <Box>
+            <Typography sx={{ fontSize: '0.75rem', lineHeight: 1.5, color: 'text.secondary' }}>Priority</Typography>
+            <Typography sx={{ fontSize: '0.875rem', lineHeight: 1.5, fontWeight: 600 }}>{PRIORITY_LABELS[proposal.priority] || proposal.priority}</Typography>
           </Box>
         </CardContent>
       </Card>
@@ -375,10 +541,19 @@ export default function AdminWorkspace() {
 
           {isApproved && (
             <>
+              <Button
+                variant="outlined"
+                color="warning"
+                startIcon={<UndoIcon />}
+                onClick={() => setReturnToReviewDialogOpen(true)}
+                disabled={returnToReviewMutation.isPending}
+              >
+                Return to Review
+              </Button>
               <Button
                 variant="contained"
                 startIcon={<PictureAsPdfIcon />}
-                onClick={() => pdfMutation.mutate()}
+                onClick={() => pdfMutation.mutate(false)}
                 disabled={pdfMutation.isPending}
               >
                 {pdfMutation.isPending ? 'Generating...' : 'Generate PDF'}
@@ -396,32 +571,39 @@ export default function AdminWorkspace() {
           )}
 
           {isSent && (
+            <>
+              <Button
+                variant="outlined"
+                startIcon={<DownloadIcon />}
+                onClick={() => handleDownloadPdf(id!, proposal.proposalNumber, proposal.currentRevision)}
+                disabled={downloadingRevId === id}
+              >
+                Download PDF
+              </Button>
+              <Button
+                variant="outlined"
+                startIcon={<HistoryIcon />}
+                onClick={() => setReviseDialogOpen(true)}
+                disabled={reviseMutation.isPending}
+              >
+                Create Revision
+              </Button>
+            </>
+          )}
+
+          {proposal.status === 'Revised' && (
             <Button
               variant="outlined"
-              startIcon={<HistoryIcon />}
-              onClick={() => setReviseDialogOpen(true)}
-              disabled={reviseMutation.isPending}
+              startIcon={<DownloadIcon />}
+              onClick={() => handleDownloadPdf(id!, proposal.proposalNumber, proposal.currentRevision)}
+              disabled={downloadingRevId === id}
             >
-              Create Revision
+              Download PDF
             </Button>
           )}
         </CardContent>
       </Card>
 
-      {/* Unsaved Changes Navigation Guard */}
-      <Dialog open={blocker.state === 'blocked'} onClose={() => blocker.reset?.()}>
-        <DialogTitle>Unsaved Changes</DialogTitle>
-        <DialogContent>
-          <Typography>You have unsaved changes. Are you sure you want to leave?</Typography>
-        </DialogContent>
-        <DialogActions>
-          <Button onClick={() => blocker.reset?.()}>Stay</Button>
-          <Button variant="contained" color="error" onClick={() => blocker.proceed?.()}>
-            Discard & Leave
-          </Button>
-        </DialogActions>
-      </Dialog>
-
       {/* Approve Confirmation Dialog */}
       <Dialog open={approveDialogOpen} onClose={() => setApproveDialogOpen(false)}>
         <DialogTitle>Approve Proposal</DialogTitle>
@@ -496,6 +678,71 @@ export default function AdminWorkspace() {
           </Button>
         </DialogActions>
       </Dialog>
+
+      {/* Return to Review Confirmation Dialog */}
+      <Dialog open={returnToReviewDialogOpen} onClose={() => setReturnToReviewDialogOpen(false)}>
+        <DialogTitle>Return to Review</DialogTitle>
+        <DialogContent>
+          <Typography>
+            Return <strong>{proposal.proposalNumber}</strong> to review?
+            This will clear the approval and allow further editing.
+          </Typography>
+        </DialogContent>
+        <DialogActions>
+          <Button onClick={() => setReturnToReviewDialogOpen(false)}>Cancel</Button>
+          <Button
+            variant="contained"
+            color="warning"
+            onClick={() => returnToReviewMutation.mutate()}
+            disabled={returnToReviewMutation.isPending}
+          >
+            {returnToReviewMutation.isPending ? 'Returning...' : 'Confirm'}
+          </Button>
+        </DialogActions>
+      </Dialog>
+
+      {/* Audit Trail */}
+      {auditTrail && auditTrail.length > 0 && (
+        <Card sx={{ mt: 2 }}>
+          <CardContent sx={{ py: 1.5 }}>
+            <Typography variant="subtitle2" sx={{ mb: 1 }}>Activity Log</Typography>
+            <Box sx={{ maxHeight: 240, overflow: 'auto' }}>
+              <Box
+                component="table"
+                sx={{
+                  width: '100%',
+                  borderCollapse: 'collapse',
+                  '& tr:hover': { bgcolor: 'action.hover' },
+                  '& td': { padding: '6px 8px', border: 0 },
+                }}
+              >
+                <tbody>
+                  {auditTrail.map((entry) => (
+                    <tr key={entry.id}>
+                      <td style={{ whiteSpace: 'nowrap', width: 155, paddingLeft: 0 }}>
+                        <Typography variant="caption" color="text.secondary">
+                          {new Date(entry.timestamp).toLocaleString()}
+                        </Typography>
+                      </td>
+                      <td style={{ width: 150 }}>
+                        <Chip label={formatAction(entry.action)} size="small" variant="outlined" />
+                      </td>
+                      <td style={{ whiteSpace: 'nowrap', width: 120 }}>
+                        <Typography variant="caption">{entry.userName}</Typography>
+                      </td>
+                      <td style={{ overflow: 'hidden', textOverflow: 'ellipsis', whiteSpace: 'nowrap', maxWidth: 0 }}>
+                        <Typography variant="caption" color="text.secondary">
+                          {entry.details ? formatDetails(entry.details) : ''}
+                        </Typography>
+                      </td>
+                    </tr>
+                  ))}
+                </tbody>
+              </Box>
+            </Box>
+          </CardContent>
+        </Card>
+      )}
     </Box>
   );
 }