- Added scroll progress tracking via JavaScript in WebView
- Implemented 3% threshold to reduce message frequency
- Removed SwiftUI onScrollGeometryChange and onScrollPhaseChange
- Cleaned up unused state variables (scrollViewHeight, currentScrollOffset)
- Removed Combine import (no longer needed)
- Disabled JumpButton scroll-to-position (requires JavaScript implementation)
This approach offloads scroll tracking to the WebView's JavaScript,
reducing SwiftUI state updates and improving performance.