implement auth login and register with MongoDB

- Add AuthController login/register endpoints with error handling
- Implement AuthService with password validation and user creation
- Add MongoUserRepository with findByEmail and create methods
- Implement password hashing with bcrypt
- Add dotenv for environment variable support
- Add Docker Compose setup for MongoDB + Mongo Express
- Stub AuthMiddleware with fake user for testing
- Update CLAUDE.md with implementation status

apps/server/src/app.ts

@@ -1,5 +1,6 @@
 import express from 'express';
 import mongoose from 'mongoose';
+import 'dotenv/config'
 
 import { createRoutes } from './routes';
 import { AuthController, ChatController, EventController } from './controllers';