Closes #<issue-number>

### Summary

- What and why in 1–3 sentences.

### UI Changes

- Add before/after images or a short clip.

### Checklist

- [ ] Linked to issue(s) above by issue number (e.g. `Closes #<issue-number>`)
- [ ] One problem per PR (no unrelated changes)
- [ ] Lints pass; CI green
- [ ] Tricky parts are commented in code
- [ ] Backward compatible with existing device firmware (See `DEVELOPMENT.md` for details)