feat: add RSS xml (#34)

* feat: add RSS xml

---------

Co-authored-by: saicaca <zephyird@gmail.com>

package.json

@@ -14,6 +14,7 @@
   },
   "dependencies": {
     "@astrojs/check": "^0.5.9",
+    "@astrojs/rss": "^4.0.5",
     "@astrojs/svelte": "^5.2.0",
     "@astrojs/tailwind": "^5.1.0",
     "@fontsource-variable/jetbrains-mono": "^5.0.20",
@@ -23,6 +24,7 @@
     "astro-compress": "^2.2.15",
     "astro-icon": "1.1.0",
     "colorjs.io": "^0.5.0",
+    "markdown-it": "^14.1.0",
     "mdast-util-to-string": "^4.0.0",
     "overlayscrollbars": "^2.6.1",
     "pagefind": "^1.0.4",
@@ -31,6 +33,7 @@
     "rehype-katex": "^7.0.0",
     "rehype-slug": "^6.0.0",
     "remark-math": "^6.0.0",
+    "sanitize-html": "^2.13.0",
     "sharp": "^0.33.2",
     "svelte": "^4.2.12",
     "tailwindcss": "^3.4.1",
@@ -45,6 +48,8 @@
     "@iconify-json/material-symbols": "^1.1.74",
     "@rollup/plugin-yaml": "^4.1.2",
     "@tailwindcss/typography": "^0.5.10",
+    "@types/markdown-it": "^14.0.0",
+    "@types/sanitize-html": "^2.11.0",
     "stylus": "^0.63.0"
   }
 }