draw_metronome() renders the screen for any parsed track: track name + big BPM,
play/stop transport, and the polymeter lane grid — per-lane beat cells coloured by
level (accent amber / normal cyan / ghost purple / rest dark), playhead highlight,
beat gridlines, poly (~) marker. Pure no_std view over borrowed data (LaneView/
Screen) so the firmware build stays allocator-free.
uisim now parses a real track (track-format) and renders draw_metronome to PNG —
iterate the UI on the host, no bench. Firmware still draws the bring-up diagnostic.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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