* Optimize worktree parent picker: conditional mount, virtualization, lazy
- Mount WorktreeParentPickerPopover only when open to avoid hundreds of
unmounted instances subscribing to lineage and worktree store updates.
- Virtualize the candidate list and resolve activity statuses only for
visible rows, eliminating redundant status subscriptions.
- Extract filtering, placement calculations, and row rendering into
separate modules for testability and clarity.
* Memoize worktree parent picker search handler
Wrap search state update in useCallback to stabilize the handler
across re-renders. Reduces unnecessary effect runs and enables better
memoization of child components.
* Optimize worktree parent picker: defer unmount, memoize IDs
- Defer unmount until exit animation completes (200ms) to prevent premature teardown
- Memoize visibleWorktreeIds to prevent status hook from rebuilding its selector on every render
ea68d97c28