feat: scaffold center and guild backend NestJS skeletons

Fabric.Backend.Center/package.json

@@ -0,0 +1,23 @@
+{
+  "name": "fabric-backend-center",
+  "version": "0.1.0",
+  "private": true,
+  "description": "Fabric Identity Hub (Center service)",
+  "scripts": {
+    "build": "tsc -p tsconfig.build.json",
+    "start": "node dist/main.js",
+    "start:dev": "ts-node src/main.ts"
+  },
+  "dependencies": {
+    "@nestjs/common": "^10.4.8",
+    "@nestjs/core": "^10.4.8",
+    "@nestjs/platform-express": "^10.4.8",
+    "reflect-metadata": "^0.2.2",
+    "rxjs": "^7.8.1"
+  },
+  "devDependencies": {
+    "@types/node": "^22.10.1",
+    "ts-node": "^10.9.2",
+    "typescript": "^5.7.2"
+  }
+}