- Add 19 new test cases covering error file processing
- Test default metadata assignment for failed templates
- Add file cleanup and error handling tests
- Test progress callback functionality
- Add batch result merging tests
- Test legacy processBatch method
Coverage improved from 51.51% to 98.87%
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>