chore(frontend): update exports and fix lint issues

- Update projects/index.ts to export new list components
- Update prototypes page to reflect #53 implementation at /
- Fix unused variable in ErrorBoundary.test.tsx

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Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

frontend/src/app/[locale]/prototypes/page.tsx

@@ -22,8 +22,8 @@ const implementedPrototypes = [
     title: 'Main Dashboard',
     description: 'Landing page with projects list, activity feed, and quick stats overview',
     icon: Home,
-    issue: '#47',
-    implementedAt: '/projects',
+    issue: '#53',
+    implementedAt: '/',
   },
   {
     id: 'project-dashboard',