QA hardening: security RLS fixes, Flutter 3.47.5 upgrade, UI/validation fixes

Security — enforce write authorization server-side (was UI/RPC-only):
- it_service_requests RLS: block cross-office read/edit + self-approve (QA-015)
- pass_slips RLS: owner can complete but not self-approve (QA-046)
- swap_requests RLS: scope select/update to participants + admin (QA-047)
- storage: tighten it_service_attachments + task_attachments write/delete (QA-027)
- admin_user_management edge function: allow programmers to manage users (QA-016)

Fixes:
- workforce generator "uncovered shifts" false alarms (QA-043/044)
- network-map VLAN + New-location dialog validation, disabled-until-valid (QA-048)
- de-flake time-of-day-dependent dashboard metrics test (QA-045)

Toolchain:
- upgrade to Flutter 3.47.5 / Dart 3.13.4; font_awesome_flutter 11.0.0,
  flutter_quill 11.6.0, pdfrx 2.6.5; clear resulting deprecations (QA-002)

analyze clean; 139 tests pass; web build succeeds. Report + evidence in docs/qa/.

Note: also carries the in-progress Brick model cleanup already present in the
working tree. QA-001 (AI keys public in the build) is deferred by owner decision.

Co-Authored-By: claude-flow <ruv@ruv.net>

macos/Flutter/GeneratedPluginRegistrant.swift

@@ -16,6 +16,7 @@ import flutter_image_compress_macos
 import flutter_local_notifications
 import geolocator_apple
 import package_info_plus
+import pdfium_flutter
 import printing
 import quill_native_bridge_macos
 import share_plus
@@ -35,6 +36,7 @@ func RegisterGeneratedPlugins(registry: FlutterPluginRegistry) {
   FlutterLocalNotificationsPlugin.register(with: registry.registrar(forPlugin: "FlutterLocalNotificationsPlugin"))
   GeolocatorPlugin.register(with: registry.registrar(forPlugin: "GeolocatorPlugin"))
   FPPPackageInfoPlusPlugin.register(with: registry.registrar(forPlugin: "FPPPackageInfoPlusPlugin"))
+  PDFiumFlutterPlugin.register(with: registry.registrar(forPlugin: "PDFiumFlutterPlugin"))
   PrintingPlugin.register(with: registry.registrar(forPlugin: "PrintingPlugin"))
   QuillNativeBridgePlugin.register(with: registry.registrar(forPlugin: "QuillNativeBridgePlugin"))
   SharePlusMacosPlugin.register(with: registry.registrar(forPlugin: "SharePlusMacosPlugin"))