feat: add WeChat environment variables to docker-compose

## Changes

### Docker Compose Configuration
- Add WECHAT_APP_ID environment variable to server service
- Add WECHAT_APP_SECRET environment variable to server service
- Add WECHAT_REDIRECT_URI environment variable to server service

## Purpose
Enable WeChat Open Platform QR code login functionality by passing
WeChat credentials from .env file to the server container.

## Testing
- All containers started successfully
- Server loaded configuration correctly
- WeChat login endpoints are now available

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

docker-compose.yml

@@ -42,6 +42,9 @@ services:
       - REDIS_PORT=6379
       - CORS_ORIGINS=${CORS_ORIGINS:-*}
       - DATABASE_URL=mysql://${MYSQL_USER:-gala_user}:${MYSQL_PASSWORD:-gala_pass}@mysql:3306/${MYSQL_DATABASE:-gala_db}
+      - WECHAT_APP_ID=${WECHAT_APP_ID}
+      - WECHAT_APP_SECRET=${WECHAT_APP_SECRET}
+      - WECHAT_REDIRECT_URI=${WECHAT_REDIRECT_URI}
     depends_on:
       mysql:
         condition: service_healthy