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

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

frontend/tests/components/common/ErrorBoundary.test.tsx

@@ -299,9 +299,7 @@ describe('ErrorBoundary', () => {
       expect(icons.length).toBeGreaterThan(0);
     });
 
-    it('reset button is keyboard accessible', async () => {
-      const user = userEvent.setup();
-
+    it('reset button is keyboard accessible', () => {
       render(
         <ErrorBoundary>
           <ThrowingComponent shouldThrow={false} />