fix(ui): explain Team setup net access changes (#1558)

## Description
Fixes live dogfood confusion in the legacy Team final review. Synthetic `shared:default` cleanup is presented as **Legacy default sharing**, the review opens with a concrete net-effect statement, repeated Project names use stable privacy-safe Project N-of-M labels on both Projects and Review, and grouping distinguishes reviewed rows from canonical Projects. Long Finish requests now show a prominent atomic-progress state; roster failure after Finish explicitly says setup did not finish and no changes were applied.

Tracks codemem-752i.11 and blocks codemem-752i.7.

## Type of Change
- [ ] 🚀 Feature (new functionality)
- [x] 🐛 Bug fix (fixes an issue)
- [ ] 📚 Documentation (docs-only change)
- [ ] 🔧 Maintenance (refactor, chore, CI, etc.)
- [ ] 🧪 Testing (test-only changes)

## Testing
- [x] Full `pnpm run check`: 230 files, 5604 tests passed, 3 todo
- [x] Full `pnpm run build`
- [x] 511 focused server/UI migration tests
- [x] Net-effect, duplicate-label, Finish progress, no-partial-change error, privacy, and reduced-motion coverage

## Checklist
- [x] Code follows project style
- [x] CodeReviewer approval
- [x] No opaque identifiers rendered
- [x] No new warnings introduced