Reuse the AVFoundation Swift files between iOS and macOS without
sprinkling `#if canImport(UIKit)` through them. The split is:
darwin/Camera/ platform-shared (AVFoundation only)
CameraPlugin channel + instance map
CameraInstance session + outputs + texture
CameraSession AVCaptureSession + runtime-error obs
CaptureDevice front/back discovery
PhotoOutput AVCapturePhotoOutput
PreviewSink CVPixelBuffer → FlutterTexture
VideoRecorder AVAssetWriter
DeviceOrientation wire-string enum
ios/Classes/Camera/ iOS-only impls + extensions
AudioSession AVAudioSession.upgradeForRecording
DeviceOrientationBridge UIDevice.orientation listener
CameraSession+iOS AVCaptureSessionWasInterrupted obs
+ InterruptionReason decode + the
application-audio-session flags
(all iOS-only on AVCaptureSession)
CameraSettings UIApplication.openSettingsURLString
FlutterRegistrar+iOS method-form of textures/messenger
macos/Classes/Camera/ macOS no-op stubs (same surface)
AudioSession no-op (no AVAudioSession on macOS)
DeviceOrientationBridge no-op (desktops don't rotate)
CameraSession+macOS no-op setupPlatform()
CameraSettings NSWorkspace → System Settings'
Privacy_Camera pane
FlutterRegistrar+macOS property-form of textures/messenger
`CameraSession.init` now calls `setupPlatform()` which each platform
provides via an extension — keeps the iOS-only interruption observer
and the `automaticallyConfiguresApplicationAudioSession` /
`usesApplicationAudioSession` flags (both iOS-only on AVCaptureSession)
out of the shared file. Flash-mode in PhotoOutput uses
`if #available(macOS 11/13, *)` rather than `#if`, since those are
plain version gates not platform splits.
The shared files compile into the iOS pod from `ios/Classes/Camera-shared/`
and into the macOS pod from `macos/Classes/Camera-shared/`, each a
mirror populated by a `prepare_command` in the podspec:
rm -rf Classes/Camera-shared && cp -R ../darwin/Camera Classes/Camera-shared
Symlinks and `../` source globs both fail — Pathname.glob bails on
symlinks, and CocoaPods silently drops paths that escape the pod
directory. The mirror destinations are .gitignore'd.
macOS UxPlugin now registers CameraPlugin alongside the others.
Flutter's Clipboard API only exposes text shapes. Banlu's chat composer
needs image bytes from the system clipboard for desktop paste, so add
a UxClipboard facade backed by per-platform native plugins:
* iOS: prefer raw PNG/JPEG bytes off the pasteboard, fall back to
re-encoding `UIPasteboard.image` as PNG.
* macOS: prefer NSPasteboard `.png`, fall back to TIFF transcoded
through NSBitmapImageRep so screenshots / Preview hand-offs still
work.
* Android: read primary ClipData's first item URI and stream the bytes
through ContentResolver — don't trust the clip description's MIME,
copy whatever the resolver returns.
Returns null (never throws) when the clipboard has no image — callers
treat null as "fall through to text paste".
