Maintenance mode activates after current draw completes

- When admin enables maintenance, it's set to 'pending' state
- Maintenance activates automatically after the current draw completes
- Admin can use immediate=true to force immediate activation
- Frontend shows 'Maintenance Scheduled' banner when pending
- Telegram bot warns users but still allows purchases when pending
- Both mode and pending status tracked in system_settings table

telegram_bot/src/services/api.ts

@@ -138,6 +138,25 @@ class ApiClient {
       return false;
     }
   }
+
+  /**
+   * Check if system is in maintenance mode
+   */
+  async checkMaintenanceStatus(): Promise<{ enabled: boolean; pending: boolean; message: string | null }> {
+    try {
+      const response = await this.client.get<ApiResponse<{ maintenance_mode: boolean; maintenance_pending: boolean; message: string | null }>>(
+        '/status/maintenance'
+      );
+      return {
+        enabled: response.data.data.maintenance_mode,
+        pending: response.data.data.maintenance_pending,
+        message: response.data.data.message,
+      };
+    } catch (error) {
+      // If endpoint doesn't exist or fails, assume not in maintenance
+      return { enabled: false, pending: false, message: null };
+    }
+  }
 }
 
 export const apiClient = new ApiClient();