* feat(discovery): add THC subdomain enumeration module
Add new THC module integrating ip.thc.org for subdomain discovery.
Features:
- Free service, no API key required
- No rate limits
- Fast plain-text response parsing
Includes 24 comprehensive tests covering:
- API endpoint validation
- Subdomain search functionality
- Edge cases (empty, unicode, special chars)
- Proxy support
- Response format validation
- Integration with theHarvester framework
Closes#2217
* fix: translate test comments to English
Accidentally pushed the Spanish version of the test file.
This commit updates all docstrings and comments to English.
* fix: correct rate limit documentation and add rate limit header test
- Remove 'no rate limits' claim from README.md
- Add test_api_returns_rate_limit_headers to verify x-ratelimit-* headers
* feat: add explicit rate limit handling
Based on bravesearch.py pattern:
- Detect HTTP 429 status code
- Read x-ratelimit-remaining header
- Implement retry logic with backoff (3 retries, 2s base delay)
- Handle rate limit exceptions
Added test for rate limit settings initialization.
