- Remove export from IHighlight and IMultiHighlight interfaces
- Remove export from ISelectedDecoration interface
- Remove export from ISearchPosition interface
- Keep ISearchResult exported as it's used across multiple files
- Make ISelectedDecoration extend IDisposable for consistency
- Extract SearchEngine for core search algorithms
- Extract DecorationManager for visual decorations
- Extract SearchState for state management
- Extract SearchResultTracker for result tracking
- Simplify SearchAddon by delegating to components
- Improve modularity and maintainability