fix: XHR + cache-busting ?_=Date.now() чтобы исключить connection reuse

site/templates/index.html

@@ -170,9 +170,13 @@ async function uploadFiles() {
     try {
       const t0 = performance.now();
       await new Promise((resolve, reject) => {
+        const fd = new FormData();
+        fd.append('files', f, f.name);
+        if (currentSid) fd.append('session', currentSid);
+        const url = '/api/upload?_=' + Date.now();
         const xhr = new XMLHttpRequest();
-        xhr.open('POST', '/api/upload');
-        xhr.timeout = 30000;  // 30 сек — не висеть бесконечно
+        xhr.open('POST', url);
+        xhr.timeout = 30000;
         xhr.upload.onprogress = function(e) {
           if (e.lengthComputable) {
             const pct = Math.round(e.loaded / e.total * 100);
@@ -197,9 +201,6 @@ async function uploadFiles() {
         };
         xhr.onerror = function() { reject(new Error('Сеть')); };
         xhr.ontimeout = function() { reject(new Error('Таймаут 30с')); };
-        const fd = new FormData();
-        fd.append('files', f, f.name);
-        if (currentSid) fd.append('session', currentSid);
         xhr.send(fd);
       });
     } catch (err) {