Past Due blocks lifecycle status updates until Schedule On moves (SH-262),
but it also rejected Cancel WO, which the detail panel offers on Past Due
work orders. Dispatchers had to fake a reschedule to cancel. Cancel is its
own action (SH-113), so only Canceled is exempt; every other status change
stays blocked.
Add set-once IsAddOn with server cutoff at create, board DTO exposure, legacy type-7 backfill, and Types=AddOn search compat. Aligns with FE PR #61 frozen contract.
Align board apptTime field locks with SyncFieldMergePolicy field names so sync cannot overwrite a manual appointment edit. Also add shared LifecycleStatusSets so the Phase 2 branch compiles.
Expand LifecycleStatus (EnRoute, OnSite, Rescheduled, Pending, PendingQuote) and WorkOrderType (Reactive, AddOn) to match the frontend prototype. Add FE label round-trip via LifecycleStatusMapper/WorkOrderTypeMapper, update derived fields, mutation rules and board unscheduled filter, and reactivate [Authorize] on WorkOrderController. Fix pre-existing dayGroup test expectation.
