feat: phase 1 — auth + user endpoints, Prisma v7 adapter, DB init

backend/package.json

@@ -15,6 +15,7 @@
   "license": "ISC",
   "description": "",
   "dependencies": {
+    "@prisma/adapter-pg": "^7.5.0",
     "@prisma/client": "^7.5.0",
     "argon2": "^0.44.0",
     "cookie-parser": "^1.4.7",
@@ -22,6 +23,7 @@
     "express": "^5.2.1",
     "jsonwebtoken": "^9.0.3",
     "multer": "^2.1.1",
+    "pg": "^8.20.0",
     "zod": "^4.3.6"
   },
   "devDependencies": {
@@ -30,6 +32,7 @@
     "@types/express": "^5.0.6",
     "@types/jsonwebtoken": "^9.0.10",
     "@types/multer": "^2.1.0",
+    "@types/pg": "^8.20.0",
     "nodemon": "^3.1.14",
     "prisma": "^7.5.0",
     "ts-node": "^10.9.2",