feat: implement asset fetching and routing for docs in worker and add server hooks

apps/docs/workers/app.ts

@@ -14,8 +14,26 @@ const requestHandler = createRequestHandler(
   import.meta.env.MODE
 );
 
+const BASENAME = '/docs';
+
 export default {
-  fetch(request, env, ctx) {
+  async fetch(request, env, ctx) {
+    const url = new URL(request.url);
+
+    // The app is built with base: '/docs', so HTML references assets at
+    // /docs/assets/... and /docs/*.webp, but the ASSETS binding only knows
+    // about the flat build/client/ layout. Re-fetch with the prefix stripped
+    // so static files resolve before we fall through to SSR.
+    if (url.pathname.startsWith(`${BASENAME}/`)) {
+      const strippedUrl = new URL(url);
+      strippedUrl.pathname = url.pathname.slice(BASENAME.length);
+
+      const assetResponse = await env.ASSETS.fetch(new Request(strippedUrl, request));
+      if (assetResponse.status !== 404) {
+        return assetResponse;
+      }
+    }
+
     return requestHandler(request, {
       cloudflare: { env, ctx }
     });