Replace subprocess-based packet decoding with native Python meshcoredecoder>=0.3.2.
The decoder is now always enabled (no toggle), removing ENABLED/COMMAND/TIMEOUT
config vars. Adds _enrich_payload_decoded() to compensate for payload classes that
lack to_dict() overrides in the library. Removes Node.js/npm from Dockerfile and
deletes the patches/ directory. Adds parenthesized exception rule to AGENTS.md.
- Add CONTACT_CLEANUP_ENABLED and CONTACT_CLEANUP_DAYS settings
- Implement remove_contact and schedule_remove_contact on device classes
- During contact sync, remove stale contacts from companion node
- Stale contacts (not advertised for > N days) not published to MQTT
- Update Python version to 3.13 across project config
- Remove brittle config tests that assumed default env values
Louis King