Phase 3 - Drag-drop functionality:
- Add useTreeDragDrop composable with drag state management
- Implement drag constraints (prevent dropping on self/descendants)
- Add visual feedback (opacity, drop indicators, highlight)
- Support drop positions: before/after/inside folder
Phase 5 - Data migration and sync:
- Add MigrationPrompt component for first-time users
- Implement bidirectional sync between connections and session tree
- Add syncNewConnections/syncDeletedConnections/syncConnectionName methods
- Create useConnectionSync composable for automatic sync
- Support migration from old layout with user prompt
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
