fix(asset-ai): refine mobile viewport and operating query scope

src/modules/assets/assistant/AssetAssistant.tsx

@@ -92,18 +92,47 @@ export default function AssetAssistant({
   const page = useRef<HTMLElement>(null);
   useLayoutEffect(() => {
     const viewport = window.visualViewport;
+    const mobile = window.matchMedia('(max-width: 767px)');
+    let frame = 0;
+    let unlock: (() => void) | undefined;
     const updateViewport = () => {
+      frame = 0;
+      if (!mobile.matches || (viewport && viewport.scale !== 1)) return;
       page.current?.style.setProperty('--aq-viewport-height', `${viewport?.height ?? window.innerHeight}px`);
       page.current?.style.setProperty('--aq-viewport-top', `${viewport?.offsetTop ?? 0}px`);
     };
-    updateViewport();
-    viewport?.addEventListener('resize', updateViewport);
-    viewport?.addEventListener('scroll', updateViewport);
-    window.addEventListener('resize', updateViewport);
+    const scheduleViewport = () => {
+      if (!frame) frame = requestAnimationFrame(updateViewport);
+    };
+    const syncMobile = () => {
+      unlock?.();
+      unlock = undefined;
+      if (mobile.matches) {
+        const scrollY = window.scrollY;
+        const body = document.body;
+        const previous = body.style.top;
+        body.style.top = `${-scrollY}px`;
+        body.classList.add('aq-mobile-open');
+        unlock = () => {
+          body.classList.remove('aq-mobile-open');
+          body.style.top = previous;
+          window.scrollTo({ top: scrollY, behavior: 'instant' });
+        };
+      }
+      updateViewport();
+    };
+    syncMobile();
+    mobile.addEventListener('change', syncMobile);
+    viewport?.addEventListener('resize', scheduleViewport);
+    viewport?.addEventListener('scroll', scheduleViewport);
+    window.addEventListener('resize', scheduleViewport);
     return () => {
-      viewport?.removeEventListener('resize', updateViewport);
-      viewport?.removeEventListener('scroll', updateViewport);
-      window.removeEventListener('resize', updateViewport);
+      cancelAnimationFrame(frame);
+      mobile.removeEventListener('change', syncMobile);
+      viewport?.removeEventListener('resize', scheduleViewport);
+      viewport?.removeEventListener('scroll', scheduleViewport);
+      window.removeEventListener('resize', scheduleViewport);
+      unlock?.();
     };
   }, []);
   const [theme, setTheme] = useState(appearance);
@@ -214,7 +243,7 @@ export default function AssetAssistant({
     setActiveResult(undefined);
     sessionRef.current = undefined;
     setIndependent(true);
-    composer.current?.focus();
+    composer.current?.focus({ preventScroll: true });
   };
   useEffect(
     () => () => {
@@ -360,7 +389,7 @@ export default function AssetAssistant({
     setTurns([]);
     setExpandedTurns(new Set());
     setDraft("");
-    composer.current?.focus();
+    composer.current?.focus({ preventScroll: true });
   };
   useEffect(() => {
     reset();
@@ -390,7 +419,7 @@ export default function AssetAssistant({
           className="aq-nav-active"
           onClick={() => {
             scroller.current?.scrollTo({ top: 0 });
-            composer.current?.focus();
+            composer.current?.focus({ preventScroll: true });
           }}
         >
           <MessageSquare size={16} />