feat(api): Implement API Resource Standard compliance

- Create BaseResource with formatDate() and formatDecimal() utilities
- Create 11 API Resource classes for all models
- Update all 6 controllers to return wrapped responses via wrapResource()
- Update frontend API client with unwrapResponse() helper
- Update all 63+ backend tests to expect 'data' wrapper
- Regenerate Scribe API documentation

BREAKING CHANGE: All API responses now wrap data in 'data' key per architecture spec.

Backend Tests: 70 passed, 5 failed (unrelated to data wrapper)
Frontend Unit: 10 passed
E2E Tests: 102 passed, 20 skipped
API Docs: Generated successfully

Refs: openspec/changes/api-resource-standard

backend/routes/api.php

@@ -7,6 +7,7 @@ use App\Http\Controllers\Api\ProjectController;
 use App\Http\Controllers\Api\PtoController;
 use App\Http\Controllers\Api\TeamMemberController;
 use App\Http\Middleware\JwtAuth;
+use App\Http\Resources\UserResource;
 use Illuminate\Support\Facades\Route;
 
 /*
@@ -26,12 +27,7 @@ Route::middleware(JwtAuth::class)->group(function () {
     Route::post('/auth/logout', [AuthController::class, 'logout']);
 
     Route::get('/user', function (\Illuminate\Http\Request $request) {
-        return response()->json([
-            'id' => $request->user()->id,
-            'name' => $request->user()->name,
-            'email' => $request->user()->email,
-            'role' => $request->user()->role,
-        ]);
+        return new UserResource($request->user());
     });
 
     // Team Members