Add folder game, file browser UI, and automated tests.

Introduces a localStorage-backed messy-desktop challenge with sub-steps,
drag-and-drop and Places/Back navigation, IBM Plex Mono, and a /api/health
endpoint. Adds Vitest coverage for the API and level logic plus Playwright
smoke tests.

Made-with: Cursor

.gitignore

@@ -7,6 +7,10 @@
 
 # testing
 /coverage
+/playwright-report/
+/test-results/
+/blob-report/
+/playwright/.cache/
 
 # database
 /prisma/db.sqlite