Add copyright headers to configuration files

Extended copyright headers to SQL, YAML, and JSON configuration files:
- config/docker/init.sql (SQL comment block)
- docker-compose.yml (YAML comment)
- composer.json and src/composer.json (JSON _comment field)

All files validated and tested successfully.

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

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

config/docker/init.sql

@@ -1,3 +1,11 @@
+/**
+ * Web Crawler - Database Schema
+ *
+ * @copyright Copyright (c) 2025 Martin Kiesewetter
+ * @author    Martin Kiesewetter <mki@kies-media.de>
+ * @link      https://kies-media.de
+ */
+
 -- Database initialization script for Web Crawler
 
 -- Crawl Jobs Table