同步进度增加详细天数反馈，优化日期范围避免重复请求无数据的历史日期

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

ft-app/app/templates/admin.html

@@ -193,8 +193,10 @@
 
 <script>
 var syncTimer = null;
+var progressShownAt = 0;
 
 function showProgress() {
+  progressShownAt = Date.now();
   document.getElementById('sync-progress').style.display = 'block';
   document.getElementById('sync-progress-bar').style.width = '0%';
   document.getElementById('sync-progress-pct').textContent = '';
@@ -203,6 +205,7 @@ function showProgress() {
 
 function hideProgress() {
   clearInterval(syncTimer);
+  syncTimer = null;
   document.getElementById('sync-progress').style.display = 'none';
 }
 
@@ -216,23 +219,27 @@ function pollProgress() {
       document.getElementById('sync-progress-label').textContent = data.label;
 
       if (data.finished) {
-        clearInterval(syncTimer);
-        document.getElementById('sync-progress-bar').style.width = '100%';
-        document.getElementById('sync-progress-pct').textContent = '100%';
-        document.getElementById('sync-progress-label').textContent = data.label + ' 完成';
-        document.getElementById('sync-progress-pct').textContent = '✓';
+        var elapsed = Date.now() - progressShownAt;
+        var delay = elapsed < 1000 ? 1000 - elapsed : 0;
+        setTimeout(function() {
+          clearInterval(syncTimer);
+          syncTimer = null;
+          document.getElementById('sync-progress-bar').style.width = '100%';
+          document.getElementById('sync-progress-label').textContent = data.label + ' ✓';
+          document.getElementById('sync-progress-pct').textContent = '';
+        }, delay);
       }
     });
 }
 
 function startSync(url) {
-  if (syncTimer) { clearInterval(syncTimer); }
+  if (syncTimer) { clearInterval(syncTimer); syncTimer = null; }
   showProgress();
   fetch(url, { method: 'POST' })
     .then(function(r) { return r.json(); })
     .then(function(data) {
       if (!data.ok) { hideProgress(); return; }
-      syncTimer = setInterval(pollProgress, 600);
+      syncTimer = setInterval(pollProgress, 500);
     });
 }