Add Cursor provider support across backend, contracts, and UI

- Accept `cursor` as a first-class provider in orchestration, persistence, and session directory flows
- Update model/provider inference and normalization to handle Cursor model aliases
- Revamp chat provider/model picker with Cursor-specific trait controls and add coverage in tests
86e204439eJulius Marminge committed on 3/6/2026, 7:00:41 AM· committed by Julius Marmingeparent04a931f
16 files changedLine totals unavailable