refactor: migrate img tags to next/image and fix hook usage

src/app/chat/components/fullscreen-image-viewer.tsx

@@ -9,6 +9,7 @@
  *   - 点击空白 / 下滑手势 → 关闭
  *   - 双指缩放（CSS `touch-action: pinch-zoom`）
  */
+import Image from "next/image";
 import { useEffect } from "react";
 
 import styles from "./fullscreen-image-viewer.module.css";
@@ -34,10 +35,12 @@ export function FullscreenImageViewer({ imageUrl, onClose }: FullscreenImageView
       role="dialog"
       aria-label="Fullscreen image"
     >
-      {/* eslint-disable-next-line @next/next/no-img-element */}
-      <img
+      <Image
         src={imageUrl.startsWith("data:") || imageUrl.startsWith("http") ? imageUrl : `data:image/png;base64,${imageUrl}`}
         alt=""
+        width={800}
+        height={800}
+        className={styles.viewerImage}
         onError={(e) => {
           (e.currentTarget as HTMLImageElement).style.display = "none";
           (e.currentTarget.parentElement as HTMLElement).innerHTML =