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/payments/lib/src/data/repositories/payments_repository_impl.dart

@@ -24,7 +24,7 @@ class PaymentsRepositoryImpl implements PaymentsRepository {
       if (endDate != null) 'endDate': endDate,
     };
     final ApiResponse response = await _apiService.get(
-      StaffEndpoints.paymentsSummary.path,
+      StaffEndpoints.paymentsSummary,
       params: params.isEmpty ? null : params,
     );
     return PaymentSummary.fromJson(response.data as Map<String, dynamic>);
@@ -40,7 +40,7 @@ class PaymentsRepositoryImpl implements PaymentsRepository {
       if (endDate != null) 'endDate': endDate,
     };
     final ApiResponse response = await _apiService.get(
-      StaffEndpoints.paymentsHistory.path,
+      StaffEndpoints.paymentsHistory,
       params: params.isEmpty ? null : params,
     );
     final Map<String, dynamic> body = response.data as Map<String, dynamic>;
@@ -63,7 +63,7 @@ class PaymentsRepositoryImpl implements PaymentsRepository {
       if (endDate != null) 'endDate': endDate,
     };
     final ApiResponse response = await _apiService.get(
-      StaffEndpoints.paymentsChart.path,
+      StaffEndpoints.paymentsChart,
       params: params,
     );
     final Map<String, dynamic> body = response.data as Map<String, dynamic>;