R-8 — Linguist language competence:
- Add User.languages[] BCP-47 field to backend model + UserResponse schema
- Frontend: show amber warning in assign modal when selected linguist has no
competence listed for the target language
PM VTT editing (FinalDetail):
- PM and ADMIN can now edit captions/AD in the final review stage
- VttEditor becomes read-write with onCueSave wired to updateVttMutation
- Other roles remain read-only
Timeline right-click + add pause:
- Right-click anywhere on the timeline opens a context menu showing the timestamp
- If near a pause point marker: "Edit timing" + "Regenerate TTS" options
- If on empty space: "Add AD cue at Xs" → inserts a new AD cue in the editor
- Pause point markers widened from 1px → 2px (3px on hover) for easier clicking
- Right-click on a pause point marker directly opens the editor
VttEditor insertAtTimeMs prop:
- New prop triggers programmatic insert at a specific video timestamp
- Used by the timeline right-click "Add AD cue here" action
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>