chore(deps): @fastify/static ^8 → ^9

Mise à niveau majeure du plugin de service statique (déjà installée dans l'arbre de travail, build + 253 tests verts).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

packages/server/package.json

@@ -53,7 +53,7 @@
   "dependencies": {
     "@arboretum/shared": "0.1.0",
     "@fastify/cookie": "^11.0.0",
-    "@fastify/static": "^8.0.0",
+    "@fastify/static": "^9.0.0",
     "@fastify/websocket": "^11.0.0",
     "@homebridge/node-pty-prebuilt-multiarch": "^0.13.0",
     "@xterm/headless": "^6.0.0",