* Add enhanced text sanitization
* Format code with prettier
* Refactor tests to remove redundancy and improve structure
- Remove redundant 'mixed input patterns' test from sanitizer.test.ts
- Consolidate integration tests into 2 focused real-world scenarios
- Add HTML comment stripping to sanitizeContent function
- Update test expectations to match sanitization behavior
- Maintain full coverage with fewer, more focused tests
* Fix prettier formatting
* Remove rendered.html from repository
* Remove test-markdown.json and update .gitignore
* Revert .gitignore changes
