Drop isVideoMirrored on the AVCaptureVideoDataOutput connection — the
data output feeds both the preview texture AND the recorder, so any
mirror set there ended up baked into the recorded MP4. Recorded video
+ captured JPEG now carry the raw sensor feed ("as others see you"),
matching telegram-iOS and the stock iOS Camera app default.
The selfie preview is mirrored inside UxCameraPreview itself
(Transform.flip(flipX: true) around the Texture when
description.lens == front) — the analog of telegram's
CameraPreviewView.mirroring CALayer transform. Consumers
(CameraThumb, etc.) don't need to know which lens is active.
Two leak paths surfaced after a flip-then-record-then-pop session
left the front camera claim stranded:
1. setDescription swapped instance.device without telling the plugin —
devicesInUse still held the original cameraId. After dispose,
releaseClaim only removed the *current* id, leaving the original
stuck. Next push of the page hit device_busy on the original cam.
Fix: setDescription handler now does a contention check, inserts
the new id and drops the old (or rolls back on swap failure).
2. create's catch path called releaseClaim(for: instance), but if
configureSession threw before instance.device was set,
instance.currentCameraId is nil — and the cameraId we inserted on
line above leaked. Fix: drop the known cameraId + audio claim
explicitly in the catch.
