fix: hide page title on mobile Profile view

The mobile profile form already renders its own header via
ProfileMobileView, so the desktop page title was redundant on small
viewports.

Quality gates: npm run typecheck, npm run lint

Refs: openspec/changes/mobile-tool-profile-ui

apps/web/.pi-map.index.md

@@ -2,7 +2,7 @@
 dir: apps/web
 
 ## role
-Frontend web application for a browser-based code editing and terminal environment with client-side routing.
+Frontend web application for a React-based developer workspace with code editing, terminal, and routing capabilities.
 ## parent
 index: apps/.pi-map.index.md
 map: apps/.pi-map.md