chore(deps): update dependency shiki to v4

Author: renovate[bot]

package-lock.json

@@ -67,7 +67,7 @@
     "@types/react-dom": "19.2.3",
     "@types/three": "0.183.1",
     "rehype-pretty-code": "0.14.3",
-    "shiki": "3.23.0",
+    "shiki": "4.0.2",
     "tailwindcss": "4.2.2",
     "tw-animate-css": "1.4.0",
     "typescript": "5.9.3"