* Fix multi-workspace drag/drop, WebView click focus, and add regression tests
- Wire bonsplit isInteractive to workspace active state so inactive
workspace NSViews are hidden from AppKit event routing
- Add CmuxWebView.mouseDown notification for browser panel focus
tracking (AppKit delivers clicks to WKWebView, not SwiftUI overlays)
- Add multi-workspace focus regression test covering isHidden fix,
rapid workspace switching, and browser panel focus routing
* Bump version to 1.36.0
