fix(chat): improve in-app keyboard avoidance

src/app/chat/components/chat-input-text-field.tsx

@@ -18,7 +18,6 @@ import {
   forwardRef,
   type FormEvent,
   type KeyboardEvent,
-  useEffect,
   useImperativeHandle,
   useRef,
 } from "react";
@@ -55,20 +54,6 @@ export const ChatInputTextField = forwardRef<
   // 对外暴露与 forwardRef 同名的 ref（指向内部 textarea 节点）
   useImperativeHandle(ref, () => innerRef.current as HTMLTextAreaElement, []);
 
-  // 获得焦点时把 textarea 滚到可见区域（修复小米/FB IAB 键盘弹起后
-  // 内容仍被遮挡的场景），rAF 等浏览器完成键盘布局。
-  useEffect(() => {
-    const el = innerRef.current;
-    if (!el) return;
-    const onFocus = () => {
-      window.requestAnimationFrame(() => {
-        el.scrollIntoView({ block: "nearest", behavior: "smooth" });
-      });
-    };
-    el.addEventListener("focus", onFocus);
-    return () => el.removeEventListener("focus", onFocus);
-  }, []);
-
   const handleKeyDown = (e: KeyboardEvent<HTMLTextAreaElement>) => {
     if (e.key !== "Enter") return;
     if (e.shiftKey || e.ctrlKey || e.metaKey) return; // 修饰键 → 换行