Desktop app: Run button missing on bash code blocks when split view is active

Environment: Claude Code desktop app (macOS, Darwin 25.5.0), version 2.1.241.

Bug: Fenced code blocks tagged bash in assistant replies normally render a Run button. When the session is displayed in split view (side-by-side pane layout), the Run button does not render on those blocks. Closing split view restores it.

Repro:

1. Open a session in the desktop app and enable split view.
2. Have the assistant reply with a fenced bash block containing a single command (e.g. git push -u origin my-branch, no leading $).
3. The block renders without a Run button.
4. Leave split view; the same style of block renders with the Run button.

Observed both in a reply containing several fenced blocks and in a reply containing only the single bash block, so it tracks the split-view state rather than message composition.