Comprehensive update to improve plugin efficiency and code quality:
- Performance: Increased BATCH_PIAN to 200 and optimized attribute parsing loops.
- Performance: Optimized codelist caching to reload only necessary data.
- UI/UX: Fixed plugin unloading (toolbar icon duplication) and added safe cursor handling.
- Refactoring: Moved GUI helper methods to class level for better OOP structure.
- Modernization: Updated dialog execution syntax to modern PyQt5/6 standards.
- Documentation: Added full inline English documentation across all modules.
david-spacil