feat: Implement staff availability feature with BLoC architecture

- Created AvailabilityPage with UI for managing staff availability.
- Integrated BLoC for state management, including LoadAvailability and ToggleDayStatus events.
- Added quick set options for availability (All Week, Weekdays, Weekends, Clear All).
- Implemented week navigation and day selection with visual feedback.
- Developed time slot management for each day, allowing toggling of availability.
- Established StaffAvailabilityModule for dependency injection and routing.
- Updated pubspec.yaml with necessary dependencies for the feature.

apps/mobile/packages/features/staff/staff_main/lib/src/staff_main_module.dart

@@ -13,6 +13,7 @@ import 'package:staff_attire/staff_attire.dart';
 import 'package:staff_shifts/staff_shifts.dart';
 import 'package:staff_payments/staff_payements.dart';
 import 'package:staff_time_card/staff_time_card.dart';
+import 'package:staff_availability/staff_availability.dart';
 
 import 'package:staff_main/src/presentation/blocs/staff_main_cubit.dart';
 import 'package:staff_main/src/presentation/constants/staff_main_routes.dart';
@@ -72,5 +73,6 @@ class StaffMainModule extends Module {
       '/time-card',
       module: StaffTimeCardModule(),
     );
+    r.module('/availability', module: StaffAvailabilityModule());
   }
 }