feat: 移除 katex copy-tex.css

feat: CDN可配置 cdnjs
feat: cdn可設置 version 和 custom format
feat: 點擊歸檔日期跳轉到頁面，標題顯示日期而不是‘歸檔’二字 closed #925
fix: Algolia搜索沒有結果 closed #923

layout/includes/third-party/math/katex.pug

@@ -1,6 +1,5 @@
 link(rel="stylesheet" type="text/css" href=url_for(theme.asset.katex))
 script(src=url_for(theme.asset.katex_copytex))
-link(rel="stylesheet" type="text/css" href=url_for(theme.asset.katex_copytex_css))
 script.
   (() => {
     document.querySelectorAll('#article-container span.katex-display').forEach(item => {