feat: Enhance AutoModeService and UI for Cursor model support

- Updated AutoModeService to track model and provider for running features, improving logging and state management.
- Modified AddFeatureDialog to handle model selection for both Claude and Cursor, adjusting thinking level logic accordingly.
- Expanded ModelSelector to allow provider selection and dynamically display models based on the selected provider.
- Introduced new model constants for Cursor models, integrating them into the existing model management structure.
- Updated README and project plan to reflect the completion of task execution integration for Cursor models.

plan/cursor-cli-integration/phases/phase-9-execution.md

@@ -1,6 +1,6 @@
 # Phase 9: Task Execution Integration
 
-**Status:** `pending`
+**Status:** `completed`
 **Dependencies:** Phase 3 (Factory), Phase 8 (Profiles)
 **Estimated Effort:** Medium (service updates)