- Implement WebPreviewProvider to manage webview lifecycle
- Create WebPreviewView React component with device simulation
- Add element selection mode with DOM inspection capabilities
- Extract element context (HTML, CSS, XPath, position, styles)
- Integrate with AI prompt system via webviewMessageHandler
- Support responsive design testing with device presets
- Add command registration and context menu integration
- Include comprehensive tests for provider and component
- Update documentation with usage instructions
Fixes#5971
