feat(telegram): add deleteMessage action

Add ability to delete messages in Telegram chats via the message tool.

Changes:
- Add deleteMessageTelegram function in send.ts
- Add deleteMessage action handler in telegram-actions.ts
- Add delete action support in telegram message plugin adapter
- Add deleteMessage to TelegramActionConfig type
- Update message tool description to mention delete action

Usage:
- Via message tool: action="delete", chatId, messageId
- Can be disabled via channels.telegram.actions.deleteMessage=false

Limitations (Telegram API):
- Bot can delete its own messages in any chat
- Bot can delete others' messages only if admin with "Delete Messages"
- Messages older than 48h in groups may fail to delete

src/channels/plugins/actions/telegram.ts

@@ -35,6 +35,7 @@ export const telegramMessageActions: ChannelMessageActionAdapter = {
     const gate = createActionGate(cfg.channels?.telegram?.actions);
     const actions = new Set<ChannelMessageActionName>(["send"]);
     if (gate("reactions")) actions.add("react");
+    if (gate("deleteMessage")) actions.add("delete");
     return Array.from(actions);
   },
   supportsButtons: ({ cfg }) => hasTelegramInlineButtons(cfg),
@@ -92,6 +93,22 @@ export const telegramMessageActions: ChannelMessageActionAdapter = {
       );
     }
 
+    if (action === "delete") {
+      const chatId = readStringParam(params, "chatId", { required: true });
+      const messageId = readStringParam(params, "messageId", {
+        required: true,
+      });
+      return await handleTelegramAction(
+        {
+          action: "deleteMessage",
+          chatId,
+          messageId: Number(messageId),
+          accountId: accountId ?? undefined,
+        },
+        cfg,
+      );
+    }
+
     throw new Error(`Action ${action} is not supported for provider ${providerId}.`);
   },
 };