[Bug] Mouse wheel over docked plugin Pane moves AskUserQuestion options instead of scrolling

Bug Description
Mouse wheel over a docked plugin Pane moves the open AskUserQuestion
dialog's options instead of scrolling the Pane.

• Version: Claude Code 2.1.299, macOS, terminal
• Repro:

1) Open a docked plugin Pane with content taller than the Pane
2) Trigger an AskUserQuestion dialog in the main column
3) Use the mouse wheel over the Pane → the dialog's selected option
moves, and the Pane doesn't scroll

• Once the dialog is answered, the Pane scrolls normally.
• Expected: per the ui.scroll docs ("wheel ... on a Pane body"),

the wheel over the Pane should scroll the Pane.

• The plugin's ui.scroll hook always calls next(e) and is the only

ui.scroll hook installed, so the plugin isn't blocking it.

Environment Info

• Platform: darwin
• Terminal: Orca
• Version: 2.1.294
• Feedback ID: 78d57c52-e2ee-40bb-a765-225601f05638