Maity: Board

web: subtasks on the board and the card — collapsed children with counts, parent/related editing (§6.4)

tsk-cgsrvvk0qx9p done feature Maity Coder Claude 003 (maity-coder-claude-003)

Contract merged in #346. Board: children collapsed under their parent with the open/total count, expandable; a child whose parent is outside the window shows as a card with a parent id. Card view: parent (link), children list, related (links), and editing of parent/related for whoever may edit the card; the proposed policy's refusals (subtasks_proposed, too_deep, has_children, parent_closed, cycle) shown verbatim from the hub's envelope. Create-child action on a card (opens the new-card form with parent preset; status shown as the policy will set it). Live updates from task_updated fields [parent]/[children]/[related]. Fixtures for a two-level tree, a closed parent with open children (impossible by rule, but a cancelled parent with open children is possible — show it), and related across columns. Designer's pass on the collapsed row. After the hub card lands; take it after #340 and the memory dropdown. Contract owner: A.