Implements get_triage and get_next_pick Tauri commands that call
bv --robot-triage and bv --robot-next respectively.
Response types are frontend-friendly (specta::Type) with:
- TriageResponse: counts, top_picks, quick_wins, blockers_to_clear
- NextPickResponse: single best pick with claim_command
Includes 5 tests covering:
- Structured data transformation
- Empty list handling
- Error propagation (BvUnavailable, BvTriageFailed)