refactor: use environment-specific .env files

- Rename .env.example to .env.development.example
- Update docker-compose.yml to use env_file for dev backend
- Update .gitignore to ignore .env.development and .env.production
- Remove generic .env and .env.example in favor of:
  * .env.development (dev) + .env.development.example (template)
  * .env.production (prod) + .env.production.example (template)

backend/.env.development.example

@@ -12,8 +12,8 @@ DATABASE_URL=postgresql://spotlightcam:spotlightcam123@db:5432/spotlightcam
 JWT_SECRET=dev-secret-key-12345-change-in-production
 JWT_EXPIRES_IN=24h
 
-# AWS SES (Phase 1.5)
-AWS_REGION=us-east-1
+# AWS SES (REPLACE WITH YOUR CREDENTIALS)
+AWS_REGION=eu-central-1
 AWS_ACCESS_KEY_ID=your-aws-access-key-id
 AWS_SECRET_ACCESS_KEY=your-aws-secret-access-key
 SES_FROM_EMAIL=noreply@spotlight.cam

backend/.gitignore

@@ -2,7 +2,8 @@
 node_modules/
 
 # Environment variables
-.env
+.env.development
+.env.production
 
 # Logs
 logs/