I'm creating an extremely difficult regex challenge that combines several advanced pattern matching requirements. The text includes:
1. Multiple IP address formats (IPv4, IPv6) with valid and invalid examples
2. Complex date formats with different separators and international styles
3. Credit card numbers with varied formatting and different valid prefixes
4. URLs with different protocols, subdomains, and path complexities
5. Code snippets with string literals containing escaped characters
6. It... (truncated)