feat: mobile Spaces nav and list-based project/workspace views

- Combine Projects and Workspaces into a single 'Spaces' grouped mobile
  nav item that opens a bottom-sheet menu.
- Add SpacesBottomSheet component with Projects/Workspaces options.
- Extend MobileListView with optional renderItem prop for rich rows.
- Redesign mobile ProjectsPage rows to show project description and
  repository chips.
- Replace mobile WorkspacesPage list with compact WorkspaceCard grid,
  matching desktop card content.
- Add mobile-list-* CSS and mobile-workspaces-list spacing.

Quality gates: npm run typecheck, npm run lint clean,
npm test -- --run 87 passed.

apps/web/src/components/features/.pi-map.md

@@ -1,13 +1,13 @@
-# features
-dir: features
+# apps/web/src/components/features
+dir: apps/web/src/components/features
 
-index: features/.pi-map.index.md
+index: apps/web/src/components/features/.pi-map.index.md
 
 ## role
-Contains modular, feature-based components that encapsulate specific domain functionality or user-facing capabilities within the project.
+Contains reusable UI components organized by feature domain for the web application.
 ## files
 ## arch
-Feature-based modular architecture with self-contained, cohesive units that likely combine related components, logic, and assets to support vertical slicing of application functionality.
+Feature-based colocation pattern with domain-specific subdirectories grouping related components, likely using composition patterns with shared UI primitives.
 ## tags
 -
 ## symbols