feat: init Astro blog with wikilinks, KaTeX and local search

- Astro 5 static blog, zero runtime JS
- Obsidian wikilink remark plugin (slug matches Astro content collection)
- KaTeX math rendering, local search, TOC, archives, tags
- 5 posts on math/physics/ML topics
- deploy scripts for nginx + certbot + rsync

package.json

@@ -0,0 +1,32 @@
+{
+  "name": "yukun-blog",
+  "type": "module",
+  "version": "1.0.0",
+  "private": true,
+  "scripts": {
+    "dev": "astro dev",
+    "start": "astro dev",
+    "build": "astro build",
+    "preview": "astro preview",
+    "check": "astro check",
+    "deploy": "./deploy/deploy.sh"
+  },
+  "dependencies": {
+    "@astrojs/mdx": "^4.0.0",
+    "@astrojs/sitemap": "^3.4.0",
+    "astro": "^5.13.0",
+    "katex": "^0.16.0",
+    "rehype-katex": "^7.0.1",
+    "remark-math": "^6.0.0"
+  },
+  "devDependencies": {
+    "@astrojs/check": "^0.9.0",
+    "typescript": "^5.7.0"
+  },
+  "allowScripts": {
+    "sharp@0.34.5": true,
+    "sharp@0.33.5": true,
+    "esbuild@0.27.7": true,
+    "esbuild@0.25.12": true
+  }
+}