fix: put Sessions back in the middle of nav on desktop and mobile

- Reorder desktop sidebar so Sessions sits between spaces/tools groups:
  Home, Projects, Workspaces, Sessions, Tool Workshop, Config Profiles, Settings.
- Reorder mobile bottom nav so Sessions is the center item:
  Home, Spaces, Sessions, Tools, Settings.
- Workspace cards already display the owning project name; no extra change needed.

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

apps/.pi-map.index.md

@@ -2,7 +2,7 @@
 dir: apps
 
 ## role
-Contains the main executable application modules that serve as entry points for the project.
+Container directory for independent application modules or deployable units within the project.
 ## parent
 index: ./.pi-map.index.md
 map: ./.pi-map.md