* fix(ci): secrets can't be used in step if conditions [skip-regression-check] (#787)
GitHub Actions step-level `if:` doesn't have access to `secrets` context.
Replace `if: secrets.X != ''` with `continue-on-error: true` and let
the Set token step handle the fallback.
Co-authored-by: Claude Sonnet 4.6 <[email protected]>
* feat: add channel-relay integration for Slack via external relay service
- Add RelayChannel and RelayClient for connecting to channel-relay SSE streams
- Add RelayConfig with env-based configuration (CHANNEL_RELAY_URL, CHANNEL_RELAY_API_KEY)
- Add channel-relay extension lifecycle: install, OAuth auth, activate with hot-add
- Add proxy message sending through channel-relay for Slack chat.postMessage
- Add extension registry entry for Slack relay with OAuth auth hint
- Add relay integration test with mock SSE server
- Wire relay channel into app startup with reconnect on stored credentials
- Add AuthRequired extension error variant for cleaner auth flow detection
[skip-regression-check]
* chore: apply cargo fmt
* fix: remove remaining Telegram test references in relay channel
* fix: address PR #790 review feedback — parser handle leak, CSRF, circuit breaker
- Fix parser handle leak on reconnect by sharing Arc<RwLock> instead of
creating a local copy in start() (shutdown now aborts the correct task)
- Add CSRF state nonce to OAuth flow: generate in auth_channel_relay,
validate in slack_relay_oauth_callback_handler, one-time use
- Remove dead proxy_slack method, update integration test to use
proxy_provider
- Add reconnect circuit breaker (max_consecutive_failures, default 50)
- Fix stale docs (Telegram refs), extract event_types constants
---------
Co-authored-by: Henry Park <[email protected]>
Co-authored-by: Claude Sonnet 4.6 <[email protected]>
