- Test hash computation and consistency
- Test cache path generation
- Test cache miss (generates diagram)
- Test cache hit (uses cached diagram)
- Test error handling
- Test cache clearing (all and by type)
- Test unicode handling
- Test timeout configuration
- Integration tests for full lifecycle
- Implement content-based hashing for cache keys
- POST diagram content to Kroki server instead of URL encoding
- Store generated SVGs in local filesystem cache
- Add cache clearing functionality
