feat: add registration and authentication

backend/package.json

@@ -1,6 +1,6 @@
 {
   "name": "calendar-run-backend",
-  "version": "1.3.0",
+  "version": "1.4.0",
   "private": true,
   "scripts": {
     "build": "tsc",
@@ -11,16 +11,24 @@
     "test": "cross-env CALENDAR_RUN_MOCK_DB=1 tsx --test test/app.test.ts"
   },
   "dependencies": {
+    "argon2": "^0.44.0",
+    "cookie-parser": "^1.4.7",
     "cors": "^2.8.5",
     "csv-parse": "^5.6.0",
     "dotenv": "^16.4.7",
     "express": "^4.21.2",
-    "pg": "^8.13.1"
+    "express-rate-limit": "^8.4.1",
+    "helmet": "^8.1.0",
+    "nodemailer": "^8.0.7",
+    "pg": "^8.13.1",
+    "zod": "^4.3.6"
   },
   "devDependencies": {
+    "@types/cookie-parser": "^1.4.10",
     "@types/cors": "^2.8.17",
     "@types/express": "^5.0.0",
     "@types/node": "^22.12.0",
+    "@types/nodemailer": "^8.0.0",
     "@types/pg": "^8.11.10",
     "@types/supertest": "^6.0.2",
     "cross-env": "^10.1.0",