fix(preview): re-trigger dev server ensure check when user clicks refresh button

vibn-frontend/app/[workspace]/project/[projectId]/(home)/preview/page.tsx

@@ -153,6 +153,18 @@ export default function PreviewTab() {
   const deviceMode = usePreviewToolbarStore((s) => s.deviceMode);
   const refreshKey = usePreviewToolbarStore((s) => s.refreshKey);
 
+  // When the user clicks the manual refresh button in the toolbar, we don't
+  // just want to reload the iframe — we also want to trigger the same ghost/zombie
+  // check as the initial mount, in case the server died while they were looking at it.
+  const prevRefreshKeyRef = useRef(refreshKey);
+  useEffect(() => {
+    if (refreshKey === prevRefreshKeyRef.current) return;
+    prevRefreshKeyRef.current = refreshKey;
+
+    // Reset the ensure called flag so the ensure effect (below) fires again.
+    ensureCalledRef.current = false;
+  }, [refreshKey]);
+
   useLayoutEffect(() => {
     setIframeSrc(primaryRunning?.url ?? null);
   }, [primaryRunning?.url]);