telegram: exit when Claude Code closes the connection

When the MCP stdio transport closes, the bot kept polling Telegram as
a zombie process — holding the token and causing 409 Conflict for the
next session.

- Listen for stdin end/close and SIGTERM/SIGINT -> bot.stop() + exit
- Force-exit after 2s if bot.stop() stalls on the long-poll timeout
- unref the approval-check interval so it doesn't keep us alive

Fixes #793, partial #788 (issue 3)

external_plugins/discord/server.ts

@@ -423,7 +423,7 @@ const mcp = new Server(
       '',
       'Messages from Discord arrive as <channel source="discord" chat_id="..." message_id="..." user="..." ts="...">. If the tag has attachment_count, the attachments attribute lists name/type/size — call download_attachment(chat_id, message_id) to fetch them. Reply with the reply tool — pass chat_id back. Use reply_to (set to a message_id) only when replying to an earlier message; the latest message doesn\'t need a quote-reply, omit reply_to for normal responses.',
       '',
-      'reply accepts file paths (files: ["/abs/path.png"]) for attachments. Use react to add emoji reactions, and edit_message for interim progress updates. Edits don\'t trigger push notifications — when a long task completes, send a new reply so the user\'s device pings.',
+      'reply accepts file paths (files: ["/abs/path.png"]) for attachments. Use react to add emoji reactions, and edit_message to update a message you previously sent (e.g. progress → result).',
       '',
       "fetch_messages pulls real Discord history. Discord's search API isn't available to bots — if the user asks you to find an old message, fetch more history or ask them roughly when it was.",
       '',
@@ -471,7 +471,7 @@ mcp.setRequestHandler(ListToolsRequestSchema, async () => ({
     },
     {
       name: 'edit_message',
-      description: 'Edit a message the bot previously sent. Useful for interim progress updates. Edits don\'t trigger push notifications — send a new reply when a long task completes so the user\'s device pings.',
+      description: 'Edit a message the bot previously sent. Useful for progress updates (send "working…" then edit to the result).',
       inputSchema: {
         type: 'object',
         properties: {

external_plugins/telegram/server.ts

@@ -304,7 +304,7 @@ function checkApprovals(): void {
   }
 }
 
-if (!STATIC) setInterval(checkApprovals, 5000)
+if (!STATIC) setInterval(checkApprovals, 5000).unref()
 
 // Telegram caps messages at 4096 chars. Split long replies, preferring
 // paragraph boundaries when chunkMode is 'newline'.
@@ -343,7 +343,7 @@ const mcp = new Server(
       '',
       'Messages from Telegram arrive as <channel source="telegram" chat_id="..." message_id="..." user="..." ts="...">. If the tag has an image_path attribute, Read that file — it is a photo the sender attached. Reply with the reply tool — pass chat_id back. Use reply_to (set to a message_id) only when replying to an earlier message; the latest message doesn\'t need a quote-reply, omit reply_to for normal responses.',
       '',
-      'reply accepts file paths (files: ["/abs/path.png"]) for attachments. Use react to add emoji reactions, and edit_message for interim progress updates. Edits don\'t trigger push notifications — when a long task completes, send a new reply so the user\'s device pings.',
+      'reply accepts file paths (files: ["/abs/path.png"]) for attachments. Use react to add emoji reactions, and edit_message to update a message you previously sent (e.g. progress → result).',
       '',
       "Telegram's Bot API exposes no history or search — you only see messages as they arrive. If you need earlier context, ask the user to paste it or summarize.",
       '',
@@ -391,7 +391,7 @@ mcp.setRequestHandler(ListToolsRequestSchema, async () => ({
     },
     {
       name: 'edit_message',
-      description: 'Edit a message the bot previously sent. Useful for interim progress updates. Edits don\'t trigger push notifications — send a new reply when a long task completes so the user\'s device pings.',
+      description: 'Edit a message the bot previously sent. Useful for progress updates (send "working…" then edit to the result).',
       inputSchema: {
         type: 'object',
         properties: {
@@ -507,6 +507,24 @@ mcp.setRequestHandler(CallToolRequestSchema, async req => {
 
 await mcp.connect(new StdioServerTransport())
 
+// When Claude Code closes the MCP connection, stdin gets EOF. Without this
+// the bot keeps polling forever as a zombie, holding the token and blocking
+// the next session with 409 Conflict.
+let shuttingDown = false
+function shutdown(): void {
+  if (shuttingDown) return
+  shuttingDown = true
+  process.stderr.write('telegram channel: shutting down\n')
+  // bot.stop() signals the poll loop to end; the current getUpdates request
+  // may take up to its long-poll timeout to return. Force-exit after 2s.
+  setTimeout(() => process.exit(0), 2000)
+  void Promise.resolve(bot.stop()).finally(() => process.exit(0))
+}
+process.stdin.on('end', shutdown)
+process.stdin.on('close', shutdown)
+process.on('SIGTERM', shutdown)
+process.on('SIGINT', shutdown)
+
 bot.on('message:text', async ctx => {
   await handleInbound(ctx, ctx.message.text, undefined)
 })