When a user replies to a Telegram message, check if the quoted text
exists in the current session transcript. If missing (from cron jobs,
background tasks, or old sessions), prepend [Replying to: "..."] to
the message so the agent has context about what's being referenced.
- Add reply_to_text field to MessageEvent (base.py)
- Populate from Telegram's reply_to_message (text or caption)
- Inject context in _handle_message when not found in history
Based on PR #1596 by anpicasso (cherry-picked reply-to feature only,
excluded unrelated /server command and background delegation changes).
Angello Picasso
d4810d8c4b