Add timeout protection to prevent indefinite hangs when Urbit server
becomes unresponsive or network partition occurs.
Changes:
- Add AbortSignal.timeout(30_000) to 7 one-shot fetch calls
- Add AbortController with 60s connection timeout to SSE stream fetch
(clears timeout after headers received to avoid aborting active stream)
Affected methods: sendSubscription, connect, openStream, poke, scry, close
Fixes#5266
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
Adds built-in Tlon (Urbit) channel plugin to support decentralized messaging on the Urbit network.
Features:
- DM and group chat support
- SSE-based real-time message monitoring
- Auto-discovery of group channels
- Thread replies and reactions
- Integration with Urbit's HTTP API
This resolves cron delivery issues with external Tlon plugins by making it a first-class built-in channel alongside Telegram, Signal, and other messaging platforms.
Implementation includes:
- Plugin registration via ClawdbotPluginApi
- Outbound delivery with sendText and sendMedia
- Gateway adapter for inbound message handling
- Urbit SSE client for event streaming
- Core bridge for Clawdbot runtime integration
Co-authored-by: William Arzt <william@arzt.co>