feat: 将目录(TOC)移至侧边栏并优化滚动高亮逻辑

- 重构TOC组件，移至SideBar中显示
- 改进IntersectionObserver实现，优化章节高亮行为
- 添加toc国际化翻译（中/英/繁）
- 更新Swup容器配置，支持文章页侧边栏刷新
- 移除原MainGridLayout中的独立TOC容器

src/i18n/i18nKey.ts

@@ -37,6 +37,7 @@ enum I18nKey {
 	notFoundDesc = "notFoundDesc",
 	backToHome = "backToHome",
 	pinned = "pinned",
+	toc = "toc",
 }
 
 export default I18nKey;

src/i18n/languages/en.ts

@@ -40,4 +40,5 @@ export const en: Translation = {
 	[Key.notFoundDesc]: "The link is broken, the page has gone missing",
 	[Key.backToHome]: "Back to Home",
 	[Key.pinned]: "Pinned",
+	[Key.toc]: "Toc",
 };

src/i18n/languages/zh_CN.ts

@@ -40,4 +40,5 @@ export const zh_CN: Translation = {
 	[Key.notFoundDesc]: "你访问的链接已断开，页面走丢了",
 	[Key.backToHome]: "返回首页",
 	[Key.pinned]: "置顶",
+	[Key.toc]: "目录",
 };

src/i18n/languages/zh_TW.ts

@@ -40,4 +40,5 @@ export const zh_TW: Translation = {
 	[Key.notFoundDesc]: "你訪問的連結已斷開，頁面走丟了",
 	[Key.backToHome]: "返回首頁",
 	[Key.pinned]: "置頂",
+	[Key.toc]: "目錄",
 };