docs: populate env.example with all required variables for issue #40

env.example

@@ -148,3 +148,69 @@ BACKUP_ENABLED=true
 BACKUP_RETENTION_DAYS=30
 BACKUP_COMPRESSION=true
 BACKUP_PATH=./backups
+
+
+# ============================================
+# GreenCode Environment Configuration
+# ============================================
+
+# ===== Server Configuration =====
+SERVER_PORT=8080
+SERVER_CONTEXT_PATH=/api
+
+# ===== Database Configuration =====
+# PostgreSQL (default)
+DB_HOST=localhost
+DB_PORT=5432
+DB_NAME=greencode_db
+DB_USER=greencode_user
+DB_PASSWORD=changeme
+
+# ===== JWT Authentication =====
+JWT_SECRET=your-super-secret-jwt-key-change-this-in-production
+JWT_EXPIRATION_MS=86400000
+JWT_REFRESH_EXPIRATION_MS=604800000
+
+# ===== OAuth Configuration (Optional) =====
+# Google OAuth
+GOOGLE_CLIENT_ID=
+GOOGLE_CLIENT_SECRET=
+
+# GitHub OAuth
+GITHUB_CLIENT_ID=
+GITHUB_CLIENT_SECRET=
+
+# ===== Frontend Configuration =====
+FRONTEND_URL=http://localhost:3000
+CORS_ALLOWED_ORIGINS=http://localhost:3000,http://localhost:8080
+
+# ===== Email Configuration (for password reset) =====
+EMAIL_HOST=smtp.gmail.com
+EMAIL_PORT=587
+EMAIL_USERNAME=your-email@gmail.com
+EMAIL_PASSWORD=your-app-password
+EMAIL_FROM=noreply@greencode.com
+
+# ===== Redis Configuration (Optional) =====
+REDIS_HOST=localhost
+REDIS_PORT=6379
+REDIS_PASSWORD=
+
+# ===== Logging =====
+LOG_LEVEL=INFO
+LOG_FILE=logs/greencode.log
+
+# ===== API Documentation =====
+SWAGGER_ENABLED=true
+API_TITLE=GreenCode API
+API_DESCRIPTION=Environmental and Sustainability Project API
+API_VERSION=1.0.0
+
+# ===== Rate Limiting =====
+RATE_LIMIT_ENABLED=true
+RATE_LIMIT_REQUESTS=100
+RATE_LIMIT_DURATION=60
+
+# ===== File Upload =====
+MAX_FILE_SIZE=10MB
+UPLOAD_DIR=./uploads