fix: 更新默认图片链接为本地路径

将外部图片链接 https://t.alcy.cc/ycy 统一替换为本地路径 /random/h，
包括置顶文章、记录文章和站点背景配置，确保图片资源的稳定性和一致性。

src/config.ts

@@ -44,7 +44,7 @@ export const siteConfig: SiteConfig = {
 	},
 	background: {
 		enable: true, // Enable background image
-		src: "https://t.alcy.cc/ycy", // Background image URL (supports HTTPS)
+		src: "/random/h", // Background image URL (supports HTTPS)
 		position: "center", // Background position: 'top', 'center', 'bottom'
 		size: "cover", // Background size: 'cover', 'contain', 'auto'
 		repeat: "no-repeat", // Background repeat: 'no-repeat', 'repeat', 'repeat-x', 'repeat-y'

src/content/posts/pin.md

@@ -1,6 +1,6 @@
 ---
 title: 加群向导
-image: https://t.alcy.cc/ycy
+image: /random/h
 published: 2025-05-24
 pinned: true
 category: 置顶

src/content/posts/record.md

@@ -2,7 +2,7 @@
 category: 记录
 description: 一些记录，不定时更新
 draft: false
-image: https://t.alcy.cc/ycy
+image: /random/h
 lang: zh_CN
 published: 1999-01-01
 tags: