The element-calling feature only advertised the LiveKit focus via the
well-known org.matrix.msc4143.rtc_foci file, and relied on STUN
auto-detection for the public IP. Element X queries the MatrixRTC
transports registry endpoint and fails with MISSING_MATRIX_RTC_TRANSPORT
when it is absent, and blocked STUN egress silently left LiveKit
advertising a private IP (call connects but no video across servers).
- synapse: enable msc4143_enabled and advertise matrix_rtc.transports
(MSC4519) with the site's element-calling URL, so Element X can
discover the LiveKit focus instead of erroring out
- livekit: determine the public IP to advertise at runtime —
explicit pin, then HTTPS egress detection (api.ipify.org /
checkip.amazonaws.com / ifconfig.me), then STUN fallback with a
warning; reject non-routable results (private/loopback/CGNAT)
- lk-jwt-service: append optional extra homeservers to
LIVEKIT_FULL_ACCESS_HOMESERVERS via the new
sovran_systemsOS.elementCalling.fullAccessHomeservers option
- add sovran_systemsOS.elementCalling.externalIP option to pin the
advertised public IP for multi-WAN/VPN setups
- add element-calling-public-check.service: boot-time diagnostics for
public DNS (via 1.1.1.1, bypassing local loopback overrides), JWT
healthz through Caddy and via the public IP, and the transports
endpoint — turns the silent -no media- failure into a visible error
- add restartTriggers so livekit/lk-jwt-service pick up regenerated
runtime configs on rebuild