When a parent is waitingfortesting/willdemo/etc but has actionable
subtasks, the API now categorises the parent as actionable. This
commit renders those subtasks as indented, clickable items under
the parent so they can be opened with a click in the TUI.
Fixes: subtasks like #3097 not surfacing when parent (#2590) is
waitingfortesting.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>