Answer HEAD on /tv/ videos

The route matched GET only, so a HEAD probe fell through to the JSON
handler and 404'd. Some players issue HEAD before streaming; they would
have concluded the file did not exist.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

server.js

@@ -1068,7 +1068,7 @@ async function handleApi(req,res,pathname){
   //
   // Range support is not optional here: without it the browser cannot seek, so
   // the scrub bar looks present but does nothing.
-  if(req.method==='GET'&&/^\/tv\/[a-z0-9-]{1,60}\.mp4$/.test(pathname)){
+  if((req.method==='GET'||req.method==='HEAD')&&/^\/tv\/[a-z0-9-]{1,60}\.mp4$/.test(pathname)){
     const slug=pathname.slice(4).replace(/\.mp4$/,'');
     const vfile=path.join(DATA_DIR,'tool-videos',slug+'.mp4');
     let st=null;
@@ -1088,6 +1088,7 @@ async function handleApi(req,res,pathname){
       return fs.createReadStream(vfile,{start,end}).pipe(res);
     }
     res.writeHead(200,securityHeaders(Object.assign({},base,{'Content-Length':st.size})));
+    if(req.method==='HEAD')return res.end();
     return fs.createReadStream(vfile).pipe(res);
   }