feat: implement mcpd core server framework with Fastify

Add Fastify server with config validation (Zod), health/healthz endpoints,
auth middleware (Bearer token + session lookup), security plugins (CORS,
Helmet, rate limiting), error handler, audit logging, and graceful shutdown.
36 tests passing.

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

src/mcpd/package.json

@@ -14,12 +14,15 @@
     "test:run": "vitest run"
   },
   "dependencies": {
-    "fastify": "^5.0.0",
     "@fastify/cors": "^10.0.0",
     "@fastify/helmet": "^12.0.0",
     "@fastify/rate-limit": "^10.0.0",
-    "zod": "^3.24.0",
+    "@mcpctl/db": "workspace:*",
     "@mcpctl/shared": "workspace:*",
-    "@mcpctl/db": "workspace:*"
+    "fastify": "^5.0.0",
+    "zod": "^3.24.0"
+  },
+  "devDependencies": {
+    "@types/node": "^25.3.0"
   }
 }