Enhance Telegram notification system with optional link support

- Updated NotifyUserAsync method in TelegramNotifier to accept an optional linkPath parameter for dynamic URL generation.
- Modified various command handlers to utilize the new linkPath feature, providing users with relevant links in their notifications.
- Adjusted ITelegramNotifier interface documentation to reflect the changes in method signature and functionality.
- Enhanced unit tests to verify the correct invocation of the updated NotifyUserAsync method.

backend/src/PnvPanel.Api/Telegram/TelegramNotifier.cs

@@ -228,6 +228,7 @@ internal sealed class TelegramNotifier(
     public async Task NotifyUserAsync(
         Guid userId,
         string message,
+        string? linkPath,
         CancellationToken cancellationToken
     )
     {
@@ -240,15 +241,14 @@ internal sealed class TelegramNotifier(
 
         InlineKeyboardMarkup? keyboard = null;
         if (!string.IsNullOrWhiteSpace(options.Value.PublicSiteUrl))
+        {
+            var url = string.IsNullOrWhiteSpace(linkPath)
+                ? options.Value.PublicSiteUrl
+                : $"{options.Value.PublicSiteUrl.TrimEnd('/')}{linkPath}";
             keyboard = new InlineKeyboardMarkup(
-                new[]
-                {
-                    InlineKeyboardButton.WithUrl(
-                        "🌐 Открыть на сайте",
-                        options.Value.PublicSiteUrl
-                    ),
-                }
+                new[] { InlineKeyboardButton.WithUrl("🌐 Открыть на сайте", url) }
             );
+        }
 
         try
         {