fix: code blocks rendering + consistent styling with ciphera-website /learn

- Convert MDX CodeBlock components to standard markdown code fences
- Add rehype-mdx-code-props to pass filename meta to code components
- Custom pre/code MDX components map fences to CodeBlock
- Add brand color badges (product + category) matching /learn layout
- Match prose styling: orange inline code, orange links, white strong
- Remove brand color background glow (not in /learn)

package.json

@@ -53,6 +53,7 @@
     "react-markdown": "^10.1.0",
     "react-use-measure": "^2.1.7",
     "recharts": "^2.15.0",
+    "rehype-mdx-code-props": "^3.0.1",
     "remark-gfm": "^4.0.1",
     "sonner": "^2.0.7",
     "svg-dotted-map": "^2.0.1",