### Implemented nova spaces multi-select
##### Summary
- Renamed "All Spaces" to "Nova Spaces" - now filters to only nova content (sm_project_*)
- Added multi-select spaces support via "Select Spaces" modal
- Projects API now returns `{ nova, developer }` instead of `{ projects }`
##### Changes
- `selectedProject` → `selectedProjects[]` (array-based selection)
- New `SelectSpacesModal` component for picking multiple spaces
- Selected spaces appear at top in modal
- Search works by containerTag
- Graphs filter by selected spaces
1. New chat messages saving to old thread (race condition)
2. Feedback modal null handling issue (boolean | null not coerced to boolean)
3. Wrong icon on Integrations tab (was Cable, now Sun)
4. Wrong icon on Graph tab (was LayoutGridIcon, now GraphIcon)
5. Missing cursor pointer on header tabs
6. Default view was "graph" instead of "list"
