feat: Update API endpoint usage in repositories to remove redundant path property

- Refactored multiple repository implementations across client and staff features to directly use endpoint objects without accessing the `path` property.
- Introduced a new `FeatureGate` class for client-side feature gating based on user scopes, allowing for better access control to API endpoints.
- Added `ApiEndpoint` class to represent API endpoints with their paths and required scopes for future feature gating.

apps/mobile/packages/features/staff/profile_sections/finances/staff_bank_account/lib/src/data/repositories/bank_account_repository_impl.dart

@@ -16,7 +16,7 @@ class BankAccountRepositoryImpl implements BankAccountRepository {
   @override
   Future<List<BankAccount>> getAccounts() async {
     final ApiResponse response =
-        await _api.get(StaffEndpoints.bankAccounts.path);
+        await _api.get(StaffEndpoints.bankAccounts);
     final List<dynamic> items = response.data['accounts'] as List<dynamic>;
     return items
         .map((dynamic json) =>
@@ -27,7 +27,7 @@ class BankAccountRepositoryImpl implements BankAccountRepository {
   @override
   Future<void> addAccount(BankAccount account) async {
     await _api.post(
-      StaffEndpoints.bankAccounts.path,
+      StaffEndpoints.bankAccounts,
       data: account.toJson(),
     );
   }

apps/mobile/packages/features/staff/profile_sections/finances/time_card/lib/src/data/repositories_impl/time_card_repository_impl.dart

@@ -16,7 +16,7 @@ class TimeCardRepositoryImpl implements TimeCardRepository {
   @override
   Future<List<TimeCardEntry>> getTimeCards(DateTime month) async {
     final ApiResponse response = await _api.get(
-      StaffEndpoints.timeCard.path,
+      StaffEndpoints.timeCard,
       params: <String, dynamic>{
         'year': month.year,
         'month': month.month,