fix(gateway): guard NoneType in Telegram reconnect after network error (#55992)

[hashbender]

Problem

After sustained network errors, the Telegram adapter's _handle_polling_network_error reconnect handler sleeps with exponential backoff (5s–60s) before calling start_polling(). During that sleep window the supervisor may tear down the adapter — disconnect() sets self._app = None (line 3028).

The existing stop() call at line 1777 was already guarded:

if self._app and self._app.updater and self._app.updater.running:
    await self._app.updater.stop()

But start_polling() at line 1785 was not guarded:

await self._app.updater.start_polling(...)  # AttributeError if self._app is None

This crashes with 'NoneType' object has no attribute 'updater', silently killing the reconnect loop. The gateway process stays alive (state file says "running" + "connected") but never processes another Telegram message.

Fix

Add a None guard for both self._app and self._app.updater before the start_polling() call, matching the pattern already used for stop(). If the app was destroyed during the reconnect delay, log a warning and abort cleanly.

Reproduction

1. Gateway happily polling Telegram
2. Network hiccup — httpx.ConnectError multiple times
3. After 10 consecutive failures, adapter enters reconnect loop
4. During the backoff sleep, supervisor restarts the adapter (self._app = None)
5. Reconnect handler wakes up and crashes on self._app.updater.start_polling()
6. Gateway appears healthy (state file says "running") but is completely silent

Testing

• python3 -m py_compile plugins/platforms/telegram/adapter.py — syntax OK
• Verified the guard pattern matches the existing stop() guard at line 1777

Fixes NousResearch#55992

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Mirror-of: NousResearch#56028
NousResearch#56028

[tenki-reviewer]

Review Complete
No issues found!

Risk: 🟢 Low (12/100) — no findings · 12 LOC across 1 file

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Single-file PR modifies the Telegram adapter's reconnection logic in plugins/platforms/telegram/adapter.py. The change replaces direct _app.stop() calls with a supervised stop sequence and adds a fatal error escalation path. No findings meet the confidence threshold.

Files Reviewed (1 files)

plugins/platforms/telegram/adapter.py