fix(server): add missing undici-types peer dependency for @types/node v20

@types/node ^20 requires undici-types to be present in node_modules
for its fetch/worker_threads type declarations. Without it tsc fails
with TS2307 "Cannot find module 'undici-types'" during lerna bootstrap.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: LucasMaupin

packages/server/package-lock.json

@@ -31,7 +31,8 @@
     "ts-mockito": "^2.6.1",
     "ts-node": "^10.9.2",
     "tsc-watch": "^4.6.2",
-    "typescript": "^5.9.3"
+    "typescript": "^5.9.3",
+    "undici-types": "^7.22.0"
   },
   "dependencies": {
     "@fastify/cors": "^10.1.0",