111 of 122 top-level src/utils/ files move into 16 topic folders (audio,
cache, cover, share, server, playback, playlist, deviceSync, waveform,
mix, format, export, changelog, ui, perf, componentHelpers). True
singletons with no cluster stay at the utils/ root.
Pure file-move: a path-aware codemod rewrote 539 relative-import
specifiers across 275 files; no logic touched. The hot-path coverage
gate list (.github/frontend-hot-path-files.txt) is updated to the new
paths for the 11 gated utils files — a mechanical consequence of the
move, not a CI change. tsc is green.
* feat(perf-probe): add FPS overlay toggle and tidy probe modal
Add optional rAF-based FPS readout controlled by a persisted probe flag.
Remove the separate keyboard shortcut. Collapse all phase sections by default.
* perf(fps-overlay): subscribe only to showFpsOverlay flag
Add usePerfProbeFlag so the overlay does not re-render when other probe
toggles change. Track the animation frame id with a loop-local variable.