Add Telegram bot integration for real-time alert notifications

- Implemented ITelegramNotificationService and TelegramNotificationService for sending alerts via Telegram.
- Updated MonitoringSettings to include Telegram configuration options.
- Enhanced AlertService to send alerts and resolutions through Telegram.
- Added API endpoints for checking Telegram status and sending test alerts.
- Updated README and TELEGRAM_SETUP.md with setup instructions and features.
- Included example configuration in appsettings.telegram.example.json.

Configuration/MonitoringSettings.cs

@@ -38,6 +38,8 @@ namespace ResourceMonitorService.Configuration
             new() { Component = "CPUTemp", WarningThreshold = 75, CriticalThreshold = 85, DurationSeconds = 60 },
             new() { Component = "GPUTemp", WarningThreshold = 80, CriticalThreshold = 90, DurationSeconds = 60 }
         };
+
+        public TelegramSettings Telegram { get; set; } = new();
     }
 
     public class AlertThresholdConfig
@@ -73,4 +75,16 @@ namespace ResourceMonitorService.Configuration
         public bool EnableConsoleLogging { get; set; } = true;
         public bool EnablePerformanceLogging { get; set; } = false;
     }
+
+    public class TelegramSettings
+    {
+        public bool IsEnabled { get; set; } = false;
+        public string BotToken { get; set; } = string.Empty;
+        public List<long> ChatIds { get; set; } = new();
+        public bool SendWarningAlerts { get; set; } = true;
+        public bool SendCriticalAlerts { get; set; } = true;
+        public bool SendResolutionNotifications { get; set; } = true;
+        public string MessageTemplate { get; set; } = "🚨 *{Level} Alert*\n\n📊 *{Component}*\n💬 {Message}\n⏰ {Timestamp:yyyy-MM-dd HH:mm:ss}";
+        public string ResolutionTemplate { get; set; } = "✅ *Alert Resolved*\n\n📊 *{Component}*\n💬 {Message}\n⏰ Resolved at {ResolvedAt:yyyy-MM-dd HH:mm:ss}";
+    }
 }