Parents with running subagents finish early → children show ⚠ orphan

[XertroV]

Symptom

Nested subagents often render as ⚠ orphan in the recursive widget tree. Suspected cause: a parent agent reaches a terminal state (completed / aborted / stopped / cleared) while children are still running or still referenced; the tree builder marks any node whose parentAgentId is missing from the live snapshot set as orphaned.

Desired behavior

• A parent that still has running or queued subagents must stay alive (not treated as finished / cleared / pruned) until those children settle — or until an explicit cascade abort.
• Healthy recursive children should not show as orphans merely because the parent turn ended.
• Must work recursively (grandparent → parent → child).

Investigation hooks

• src/ui/agent-widget-tree.ts — orphaned when parent id is missing from tree nodes
• AgentManager completion / clearCompleted / session switch
• Parent natural completion currently does not hold for live children
• session_shutdown → abortAll is a separate intentional teardown path

Acceptance

• Parent with live children remains non-terminal (or remains visible in the tree as an active parent) until children complete or are aborted with the parent
• Nested agents under a still-running lineage do not show ⚠ orphan solely due to parent turn end
• Recursive depth 2+ covered by tests
• Session teardown still aborts/cleans children cleanly

Related

Local log: bugs.txt (parents-with-running-children-stay-alive / orphan widget)

[XertroV]

Investigation + fix (widget-first)

Root cause: AgentWidget.visibleSnapshots() aged finished parents out of the tree (turn/wall-clock linger) while live descendants still carried parentAgentId. buildAgentTree then marked those children orphaned → ⚠ orphan.

Fix (TDD):

• Keep finished ancestors of any running/queued agent in the visible set (recursive parent chain).
• Prefer recovering ancestors from descendantSnapshots / manager.getRecord.
• Manager 10‑minute cleanup also skips IDs that still anchor live same-manager children.

Not changed: Parent completion / notifications still fire when the parent’s own run ends (children continue in background). This fixes tree visibility, not “block parent tool result until children finish.”

Tests: keeps a finished parent visible while a live descendant still needs it + grandparent chain in test/agent-widget.test.ts.