fix(dashboard): resolve region zones from full state names (SH-348)

Locations store State as either a two-letter postal code or a full state
name (the location list filter expands codes to both forms via
UsStateCodes.ExpandStorageValues, and dev fixtures carry State = "indiana").
DashboardRegions.Resolve only matched the two-letter key, so every location
stored as a full name fell into Unmapped/Other and the East/Central/West/
California bars undercounted.

Normalise the stored value through a new UsStateCodes.ToCode, which accepts a
code or a full name and returns the canonical postal code, before the zone
lookup. Extend the region test with full-name storage forms and add an
invariant asserting every US state and its full-name form resolves to a
canonical bucket.

Api.SeaHavenIndustries.Tests/DashboardServiceTests.cs

@@ -309,11 +309,17 @@ public class DashboardServiceTests
         ctx.Locations.AddRange(
             new Locations { Id = 1, State = "NY" },
             new Locations { Id = 2, State = "ca" },
-            new Locations { Id = 3, State = "XX" });
+            new Locations { Id = 3, State = "XX" },
+            new Locations { Id = 4, State = "indiana" },
+            new Locations { Id = 5, State = "NEW YORK" },
+            new Locations { Id = 6, State = "California" });
         ctx.workOrders.AddRange(
             new WorkOrder { AccountId = 1, LocationId = 1 },
             new WorkOrder { AccountId = 1, LocationId = 2 },
             new WorkOrder { AccountId = 1, LocationId = 3 },
+            new WorkOrder { AccountId = 1, LocationId = 4 },
+            new WorkOrder { AccountId = 1, LocationId = 5 },
+            new WorkOrder { AccountId = 1, LocationId = 6 },
             new WorkOrder { AccountId = 1, LocationId = null });
         await ctx.SaveChangesAsync();
 
@@ -322,6 +328,27 @@ public class DashboardServiceTests
 
         result.Items.Select(row => row.Region).Should().Equal(
             "East", "Central", "West", "California", "Unmapped/Other");
-        result.Items.Select(row => row.WorkOrderCount).Should().Equal(1, 0, 0, 1, 2);
+        // NY + "NEW YORK" -> East; "indiana" -> Central; "ca" + "California" -> California;
+        // "XX" + unassigned location -> Unmapped/Other. Full-name storage forms must not
+        // fall through to Unmapped/Other (SH-348 review).
+        result.Items.Select(row => row.WorkOrderCount).Should().Equal(2, 1, 0, 2, 2);
+    }
+
+    [Fact]
+    public void Resolve_MapsEveryUsStateAndItsFullNameToACanonicalBucket()
+    {
+        foreach (var code in UsStateCodes.All)
+        {
+            var byCode = DashboardRegions.Resolve(code);
+            byCode.Should().NotBe(
+                "Unmapped/Other",
+                $"state code {code} must belong to a canonical region");
+
+            var fullName = UsStateCodes.ExpandStorageValues(new[] { code })
+                .First(value => value != code);
+            DashboardRegions.Resolve(fullName).Should().Be(
+                byCode,
+                $"the full-name storage form of {code} must resolve to the same region as the code");
+        }
     }
 }

SeaHaven.Services/Helpers/DashboardRegions.cs

@@ -9,10 +9,11 @@ public static class DashboardRegions
 
     public static string Resolve(string? state)
     {
-        if (string.IsNullOrWhiteSpace(state))
+        var code = UsStateCodes.ToCode(state);
+        if (code is null)
             return "Unmapped/Other";
 
-        return StateToRegion.TryGetValue(state.Trim().ToUpperInvariant(), out var region)
+        return StateToRegion.TryGetValue(code, out var region)
             ? region
             : "Unmapped/Other";
     }

SeaHaven.Services/Helpers/UsStateCodes.cs

@@ -56,8 +56,29 @@ namespace SeaHaven.Services.Helpers
             ["WY"] = "WYOMING"
         };
 
+        private static readonly IReadOnlyDictionary<string, string> CodesByName =
+            Names.ToDictionary(pair => pair.Value, pair => pair.Key, StringComparer.Ordinal);
+
         public static IReadOnlySet<string> All { get; } = new HashSet<string>(Names.Keys, StringComparer.Ordinal);
 
+        /// <summary>
+        /// Normalises a stored state value to its two-letter postal code. Accepts either a
+        /// postal code ("IN") or a full state name ("Indiana"), case-insensitively, matching
+        /// the storage forms produced by <see cref="ExpandStorageValues"/>. Returns null when
+        /// the value is blank or is not a recognised US state.
+        /// </summary>
+        public static string? ToCode(string? value)
+        {
+            if (string.IsNullOrWhiteSpace(value))
+                return null;
+
+            var normalized = value.Trim().ToUpperInvariant();
+            if (All.Contains(normalized))
+                return normalized;
+
+            return CodesByName.TryGetValue(normalized, out var code) ? code : null;
+        }
+
         public static IReadOnlyCollection<string> ExpandStorageValues(IEnumerable<string> codes)
         {
             return codes