init new frontend

frontend/src/routes/+layout.ts

@@ -0,0 +1,6 @@
+// Pure client-rendered SPA: no SSR, no prerendering. The static adapter emits a
+// single `index.html` fallback that the Rust web layer serves for every client
+// route (including deep links like /s/<token> and /files/<path>).
+export const ssr = false;
+export const prerender = false;
+export const trailingSlash = 'never';