Enhance user plan management and update related endpoints

- Added new configuration options for user plans in `.env.example`, including `Plans__MaxCustomConfigCount` and `Plans__MinCustomConfigCount`.
- Introduced `MapPlanEndpoints` in `Program.cs` to handle plan-related API routes.
- Implemented `SetUserPlan` endpoint in `RoleEndpoints` to allow admins to assign plans to users.
- Removed deprecated role request approval endpoints from `AdminSupportEndpoints`.
- Updated `ITelegramNotifier` and related classes to reflect changes in role request handling and payment notifications.
- Refactored role management commands to remove `MaxConfigs` and focus on `MaxIpLimit` and billing settings.
- Enhanced billing request handling to accommodate plan changes instead of role changes.
- Updated various interfaces and command handlers to support new plan management features.

frontend/src/features/plans/api.ts

@@ -0,0 +1,21 @@
+import { apiRequest } from '@/shared/api/client'
+import type { ChangePlanResultDto, MyPlanStatusDto, PlanDto } from '@/shared/api/types'
+
+export function listPlans() {
+  return apiRequest<PlanDto[]>('/plans')
+}
+
+export function getMyPlanStatus() {
+  return apiRequest<MyPlanStatusDto>('/plans/status')
+}
+
+export function changePlan(planId: string | undefined, customConfigCount: number | undefined, configIdsToRevoke: string[]) {
+  return apiRequest<ChangePlanResultDto>('/plans/change', {
+    method: 'POST',
+    body: {
+      planId: planId ?? null,
+      customConfigCount: customConfigCount ?? null,
+      configIdsToRevoke,
+    },
+  })
+}