misc changes on website:

- correct a few content mistakes
- activate compression on production server
- suppress a few TS warnings (with anys, I know)

website/package.json

@@ -18,8 +18,10 @@
     "@astrojs/markdown-remark": "^5.1.0",
     "@astrojs/react": "^3.3.1",
     "@astrojs/starlight": "^0.21.5",
+    "@fastify/compress": "^7.0.3",
     "@fastify/static": "^7.0.3",
     "@gouvfr-lasuite/integration": "^0.1.0",
+    "@types/prismjs": "^1.26.3",
     "@types/react": "^18.3.1",
     "@types/react-dom": "^18.3.0",
     "@types/react-syntax-highlighter": "^15.5.11",