feat(player): add bounded rehearsal playback rates

AGENTS.md

@@ -3,7 +3,7 @@
 ## Project overview
 
 - BandScope is a local-first desktop app for rehearsal prep: a practical song view with likely harmony by section and by instrument or vocal role, form and groove cues, stems, playable ranges, simplification guidance, transposition or setup cues, part-overlap cues, visible confidence, and rehearsal priorities.
-- The ready workspace must name a next rehearsal action. Tonight's first playable section loop (count-in, pause, stop) is the #961 transport slice; stem playback and pitch-preserving rate remain later work.
+- The ready workspace must name a next rehearsal action. Tonight's first playable section loop (count-in, pause, stop) is the #961 transport slice; #1063 adds bounded pitch-preserving playback rate, while stem playback remains later work.
 - Authoritative delivery rules live in `ARCHITECTURE.md`, `docs/plans/`, and the root verification scripts.
 - Brand, tone, UX copy, and prioritization rules live in `docs/brand-story.md` and must be applied to PRDs, TRDs, UI copy, onboarding, empty states, and error messages.
 - App security rules live in `docs/security/app-security.md` and must be applied to file handling, URL intake, subprocesses, IPC, WebView usage, model loading, updates, logging, cache handling, and export behavior.

CHANGELOG.md

@@ -7,6 +7,7 @@
 - Tonight's rehearsal map now arms the first valid section map-clock loop, runs a tempo count-in, and names the next start, pause, stop, or choose-local-song action without claiming decoded audio playback; admitted section timing and picker copy use the same descriptor-snapshotted transport window.
 - Name tonight's first playable range on the ready rehearsal map and tell the player to check that span on their instrument before the section.
 - Display the analyzed song tempo (BPM) as a badge in the rehearsal workspace.
+- Move between playable section cues with Left and Right Arrow and keep the selected cue focused.
 - 각 합주 역할(Role)별 개인 연습 진행도를 0~100% 범위로 기록 및 시각화할 수 있는 연습 진척도(`practiceProgress`) 트래커 기능 추가. UI 컨트롤(슬라이더 및 +/- 버튼)과 한/영 다국어 지원 포함.
 
 ### Changed
@@ -15,6 +16,8 @@
 
 ### Fixed
 
+- Kept the rehearsal player section picker aligned with the selected player or
+  vocal role while preserving the full song-form roadmap.
 - Upgraded the local score PDF parser to `pdfjs-dist` 6.2.108, pinned Undici 7.29.0 across the workspace, and constrained PDF loading to copied in-memory bytes with a same-origin bundled worker and npm-generated lock provenance.
 
 ## [0.1.3] - 2026-04-29
@@ -75,4 +78,4 @@
 
 - `ChordsFeature` (코드 분석) 화면에서 각 파트(Role)의 `transpositionPlan`(이조/조옮김 계획)을 표시하는 기능을 추가했습니다.
 - `RangesFeature` (음역대 분석) 화면에서 겹침 경고(Overlap warning) 외에 해당 파트의 채보(Transcription) 가능 노드 수를 요약하여 보여주는 기능을 추가했습니다.
-- 신규 UI 요소에 대한 단위 테스트를 추가했습니다 (`apps/desktop/src/features/chords/index.test.tsx`, `apps/desktop/src/features/ranges/index.test.tsx`).
+- 신규 UI 요소에 대한 단위 테스트를 추가했습니다 (`apps/desktop/src/features/chords/index.test.tsx`, `apps/desktop/src/features/ranges/index.test.tsx`).