fix: resolve environment configuration issues from code review

- Remove UTF-8 BOM from .env file
- Add missing ERP settings (ERP_HEADLESS, ERP_IGNORE_HTTPS_ERRORS, ERP_AUTO_CLOSE_BROWSER) to .env.example
- Add legacy configurations to .env.example

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

.env.example

@@ -3,7 +3,12 @@ ERP_URL=https://your-erp-system.com
 ERP_USERNAME=your_username
 ERP_PASSWORD=your_password
 
-# Database Configuration (Optional)
+# Additional ERP Settings
+ERP_HEADLESS=true
+ERP_IGNORE_HTTPS_ERRORS=true
+ERP_AUTO_CLOSE_BROWSER=true
+
+# Database Configuration - SQL Server
 SQL_SERVER_HOST=localhost
 SQL_SERVER_PORT=1433
 SQL_SERVER_DATABASE=erp_db
@@ -19,4 +24,12 @@ MYSQL_PASSWORD=your_password
 # Application Settings
 LOG_LEVEL=info
 DOWNLOAD_DIR=./downloads
-TEMP_DIR=./temp
+TEMP_DIR=./temp
+
+# Legacy configurations (if needed)
+DB_SQLSERVER_DRIVER=ODBC Driver 18 for SQL Server
+DB_TRUST_SERVER_CERTIFICATE=yes
+DB_TYPE=mysql
+DB_MYSQL_HOST=192.168.31.83
+DB_MYSQL_PORT=3306
+DB_MYSQL_CHARSET=utf8mb4