feat(recording): render the safe frame from a recording store

RecordingControls publishes the safe frame a recording composes in, 16:9
or 9:16 (null while none records), to the new recording store, and the
scene chrome renders the overlay's active and ratio classes from it
instead of the controls writing them. Any frame but 9:16, even none named,
records in 16:9 as before.

docs/VUE-MIGRATION.md

@@ -233,7 +233,9 @@ a feature supplying only its accent.
    that `bindCameraOrientationControls` publishes each drawn frame it
    changes, which only `GlobeCompass` renders; an owner publishes only
    while it answers the button, so a shell replaced by a newer one leaves
-   its state alone), the Scene actions panel (`SceneInteractions`
+   its state alone), the recording safe frame (the scene chrome renders
+   the frame `RecordingControls` publishes to the `gev-recording` store),
+   the Scene actions panel (`SceneInteractions`
    teleports what the scene interactions owner publishes to the
    `gev-scene-interactions` store into the viewer's container; the owner
    keeps the pick handler and focuses the picked action), the data-pack