- README: embed resources/Screenshot.png under the intro
- remove accidentally-committed app export outputs (spectrogram_full.png,
spectrogram_export.png) and gitignore them so they don't return
- remove unused resources/wabbit_alpha.png and stray .qwen/settings.json.orig
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Display Duration, Energy, Peak amplitude, RMS amplitude, and PAPR for
the current time/frequency selection. The stats box:
- Appears next to the selection box (right side, or left if not enough room)
- Centers vertically on the selection box
- Uses a semi-transparent dark background with yellow border
- Updates live while dragging the selection
- Computed in utils.c with ComputeSignalStats()