Rework the action cluster to a mic-above-bottom-row layout, add left/right
handedness setting that swaps delete and return, and keep the screen awake
during Flow recording sessions.
Replace MLX GPU inference with CoreML bundles so transcription continues
while the host app is backgrounded. Adds model download and warm-up,
vendored Qwen3Speech, and updates onboarding, settings, and copy for the
~1.6 GB CoreML package (iOS 18+).