Fix: pages/CSS 404 on URL-encoded links (double-decode broke UTF-8 filenames)

Express already decodes req.path; the extra decodeURIComponent re-decoded
UTF-8 filenames and returned 404 for URL-encoded links (as used by the
original site), so page CSS didn't load and buttons looked unstyled.

Now all 41 pages + all CSS/assets serve 200 via encoded URLs; 0 404.

server.js

@@ -48,12 +48,10 @@ function injectEnv(html) {
 
 // Serve .html with env injection; everything else statically.
 app.use((req, res, next) => {
-  let pathname;
-  try {
-    pathname = decodeURIComponent(req.path);
-  } catch {
-    return next();
-  }
+  // Express resolves req.path to a decoded path (e.g. %E0%B8%A1 -> ม).
+  // Do NOT decodeURIComponent again — decoding twice breaks UTF-8 filenames,
+  // which made URL-encoded links (from the original site) 404 and lose their CSS.
+  const pathname = req.path;
   if (pathname.endsWith('.html') || pathname === '/' || !/\.[a-z0-9]+$/i.test(pathname)) {
     let file = pathname === '/' ? 'index.html' : pathname;
     let abs = join(DIST, file);