0.4.0: singleton locks & attachment handlers

[llblab]

Pull Request: Merge dev into main

Summary

This PR releases @llblab/pi-telegram v0.4.0.

Highlights

• Adds shared locks.json singleton ownership for Telegram polling.
• Keeps telegram.json as pure bot/user configuration.
• Supports safe ownership takeover from another live pi instance.
• Resumes polling after /new and same-cwd process restarts.
• Adds inbound attachment handlers for preprocessing files before queueing.
• Supports command handlers and locally available tool handlers such as transcribe_groq.
• Formats inbound attachments as compact [attachments] <directory> sections.
• Adds handler stdout under [outputs].
• Extracts inbound route composition into lib/routing.ts to keep index.ts smaller.

Validation

• npm run validate passed.
• Test suite: 344/344 passed.
• Audit: 0 vulnerabilities.
• Package dry-run passed for @llblab/pi-telegram@0.4.0.