Live streaming tech selection (#24374)

* 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

web/public/locales/en/components/player.json

@@ -36,14 +36,6 @@
       "title": "Bandwidth:",
       "short": "Bandwidth"
     },
-    "latency": {
-      "title": "Latency:",
-      "value": "{{seconds}} seconds",
-      "short": {
-        "title": "Latency",
-        "value": "{{seconds}} sec"
-      }
-    },
     "totalFrames": "Total Frames:",
     "droppedFrames": {
       "title": "Dropped Frames:",