The WebRTC gate read only the Frigate config, so an install with no go2rtc candidates showed WebRTC as not configured, even though go2rtc fills in default candidates at startup (including the internal one under the HA app) and WebRTC often worked. Unset candidates now run the connectivity probe first, and only a failed probe reports not configured. The not-configured reason shows as a neutral note that names the setting and says WebRTC is optional, rather than as a red error.
* allow users to select live streaming technology
* fix webrtc being downgraded to mse on load
`useUserPersistence` seeds state with the default and loads asynchronously, so the first render always used `mse` instead of the saved choice, and `useWebRTCGloballyAvailable` reports `checking` until the probe settles and re-enters that state on every consumer mount, so a saved `webrtc` was rewritten to `mse` even after the probe had already passed. On Safari the MSE player then timed out and latched the jsmpeg fallback. A pending probe now counts as available, the player waits on `autoLive` until the stored preferences load, and `handleError` gates on the mode in use since the fallback flag no longer implies webrtc is untried. A rejected IndexedDB read also resolves `loaded` now, so a blocked store can't leave the player waiting forever.
* add support for configurable ICE servers in WebRTC player
* add mic error state, fix dialog overwriting saved choice and dashboard ignoring stream
* tweaks
Josh Hawkins