feat(backend): enhance allocation and project management

Update controllers and services for allocation fidelity:
- AllocationController: variance data in responses, bulk operations
- ProjectController: include plan data in responses
- ProjectMonthPlanController: planning grid API
- AllocationMatrixService: support untracked allocations
- ProjectResource/TeamMemberResource: include reconciliation data

Improved test coverage for allocation flows.

backend/app/Http/Controllers/Api/ProjectController.php

@@ -177,7 +177,7 @@ class ProjectController extends Controller
 
         try {
             $project = $this->projectService->update($project, $request->only([
-                'code', 'title', 'type_id',
+                'code', 'title', 'type_id', 'status_id', 'approved_estimate',
             ]));
 
             return $this->wrapResource(new ProjectResource($project));