Add iMessage bridge support

[tobocop2]

Feature request

Add support for the mautrix-imessage bridge.

Challenges

iMessage bridging requires either:

• macOS host with Messages.app access
• Jailbroken iOS device running the bridge

This makes it more complex than other bridges which run entirely in Docker.

Possible approaches

1. Detect macOS host and run bridge natively (not in Docker)
2. Provide instructions for connecting an external iMessage bridge
3. Document the setup for users with jailbroken devices

Help wanted

Looking for contributors who:

• Have experience with mautrix-imessage
• Can help design an integration that works within muxbee's architecture
• Can test on macOS or jailbroken iOS

If you've successfully run mautrix-imessage, please share your setup!