feat: add article page and not found component with markdown rendering

package.json

@@ -21,6 +21,7 @@
         "@aws-sdk/s3-request-presigner": "^3.1028.0",
         "@clerk/nextjs": "^7.0.7",
         "@hookform/resolvers": "^5.2.2",
+        "@tailwindcss/typography": "^0.5.19",
         "@tanstack/react-query": "^5.95.2",
         "@vercel/analytics": "^2.0.1",
         "class-variance-authority": "^0.7.1",
@@ -35,6 +36,8 @@
         "react": "19.2.4",
         "react-dom": "19.2.4",
         "react-hook-form": "^7.72.1",
+        "react-markdown": "^10.1.0",
+        "remark-gfm": "^4.0.1",
         "shadcn": "^4.1.1",
         "slugify": "^1.6.9",
         "sonner": "^2.0.7",