React Doctor (react-doctor@0.0.28) audit of the codebase. Fixes applied:

Errors fixed:
- SessionName.tsx: Remove derived state useEffect, sync editValue in click handler
- XYPad.tsx: Add missing aria-valuemin/max/now on role="slider"

Warnings fixed:
- BottomSheet.tsx: Add role="dialog" and aria-modal to backdrop
- ToastNotification.tsx: Add role="button", tabIndex, keyboard handler to URL toast
- LandingPage.tsx: Add role="button", tabIndex, keyboard handler to example cards
- TrackRow.tsx: Add keyboard handler to mobile edit panel
- TransportBar.tsx: Add role="slider" with aria props to tempo/swing controls
- Waveform.tsx: Add role="img", extract default prop to module constant
- EffectsPanel.tsx: Add htmlFor/id to all label/input pairs (10 controls)
- Transport.tsx: Add htmlFor/id to all label/input pairs (10 controls)
- MixerPanel.tsx: Add htmlFor/id to swing label/input pair
- PitchOverview.tsx: Remove unnecessary useMemo on visibleTrackCount
- StepSequencer.tsx: Remove unnecessary useMemo on mutedTrackCount
- QRCode.tsx: Consolidate multiple setState calls into single state object

Remaining items are false positives or architectural (large components, etc).

https://claude.ai/code/session_01QtahFXjazAx1yD9qQdUyGM