chore: final build + lint + cleanup

- Run bun run build: succeeded
- Run bun run lint: no errors (3 img warnings acceptable)
- Fix any types in app/posts/[slug]/page.tsx with proper hast/rehype-pretty-code types
- Fix any type in mdx-components.tsx pre component with React.HTMLAttributes
- Remove unused language variable from mdx-components.tsx
- Verify all 3 posts render with <p> tags, code block syntax highlighting, and heading ids

bun.lock

@@ -5,6 +5,7 @@
       "name": "new-blog",
       "dependencies": {
         "@mdx-js/react": "^3.1.1",
+        "@rehype-pretty/transformers": "^0.13.2",
         "@wrksz/themes": "^0.9.3",
         "gray-matter": "^4.0.3",
         "katex": "^0.17.0",
@@ -203,6 +204,8 @@
 
     "@nolyfill/is-core-module": ["@nolyfill/is-core-module@1.0.39", "", {}, "sha512-nn5ozdjYQpUCZlWGuxcJY/KpxkWQs4DcbMCmKojjyrYDEAGy4Ce19NN4v5MduafTwJlbKc99UA8YhSVqq9yPZA=="],
 
+    "@rehype-pretty/transformers": ["@rehype-pretty/transformers@0.13.2", "", {}, "sha512-p2ciQSwqy5Ip8aNUa9q6rdS/hJZXrxHYYfDVOHvKOsBu3t9HDmQ65YX6r9Qbl19vi160OAxmGF7MIoCRDJrRhg=="],
+
     "@rtsao/scc": ["@rtsao/scc@1.1.0", "", {}, "sha512-zt6OdqaDoOnJ1ZYsCYGt9YmWzDXl4vQdKTyJev62gFhRGKdx7mcT54V9KIjg+d2wi9EXsPvAPKe7i7WjfVWB8g=="],
 
     "@shikijs/core": ["@shikijs/core@4.1.0", "", { "dependencies": { "@shikijs/primitive": "4.1.0", "@shikijs/types": "4.1.0", "@shikijs/vscode-textmate": "^10.0.2", "@types/hast": "^3.0.4", "hast-util-to-html": "^9.0.5" } }, "sha512-jLJtSJeuFffqX6/inRE1zqU5aFv2hrszvYgq3OjbAgFRZiWv7abKMDdQzYxuSDfmUPQozZvI/kuy6VMTvnvqTQ=="],