feat: add custom Apache configuration for Nextcloud

Add custom Apache configuration file to optimize Nextcloud performance and security.
Mount nextcloud.conf into Apache's conf-enabled directory for automatic loading.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

docker-compose.yml

@@ -6,6 +6,7 @@ services:
       - "127.0.0.1:8888:80"
     volumes:
       - ./data:/var/www/html
+      - ./apache/nextcloud.conf:/etc/apache2/conf-enabled/nextcloud.conf:ro
     environment:
       # Database
       - MYSQL_HOST=db