refactor(assets): relocate character cover image

src/app/splash/components/__tests__/tailwind-components.test.tsx

@@ -22,7 +22,7 @@ describe("splash Tailwind components", () => {
     expect(html).toContain("absolute");
     expect(html).toContain("bg-sidebar-background");
     expect(html).toContain("object-cover");
-    expect(html).toContain("%2Fimages%2Fsplash%2Fpic-bg-home.png");
+    expect(html).toContain("%2Fimages%2Fcover%2Felio.png");
   });
 
   it("renders SplashContent with Tailwind typography classes", () => {

src/app/splash/components/splash-background.tsx

@@ -3,7 +3,7 @@
  *
  * 
  *   `SizedBox.expand(child: Assets.images.picBgHome.image(fit: BoxFit.cover))`
- * 资源: /public/images/splash/pic-bg-home.png (kebab-case 重命名后)
+ * 资源: /public/images/cover/elio.png
  *       原名: pic_bg_home.png (snake_case)
  *
  * sizes 属性说明：
@@ -17,7 +17,7 @@ export function SplashBackground() {
   return (
     <div className="absolute inset-0 z-0 overflow-hidden bg-sidebar-background">
       <Image
-        src="/images/splash/pic-bg-home.png"
+        src="/images/cover/elio.png"
         alt=""
         fill
         priority