feat: add backend

apps/server/package.json

@@ -0,0 +1,27 @@
+{
+  "name": "server",
+  "version": "1.0.0",
+  "description": "",
+  "scripts": {
+    "dev": "tsx watch ./app.ts"
+  },
+  "keywords": [],
+  "type": "module",
+  "author": "",
+  "license": "ISC",
+  "dependencies": {
+    "@koa/router": "^14.0.0",
+    "@prisma/client": "^6.15.0",
+    "koa": "^3.0.1"
+  },
+  "devDependencies": {
+    "@tsconfig/node-ts": "^23.6.1",
+    "@tsconfig/node22": "^22.0.2",
+    "@types/koa": "^3.0.0",
+    "@types/koa__router": "^12.0.4",
+    "@types/node": "^24.3.0",
+    "prisma": "^6.15.0",
+    "tsx": "^4.20.5",
+    "typescript": "^5.9.2"
+  }
+}