fix(agent-status): track inventory children additively and fail closed on truncated inventories

Review findings round 6: (1) veto-only left the vetoing child untracked,
so its own later drain was start-less-suppressed and the pane stuck on
working — fold running non-teammate inventory entries additively
(inventoryComplete: false; no reap, so a just-parked unconfirmed teammate
row survives). (2) The agent-task parser caps at 32 entries; a running
child past the cap is invisible, so a truncated inventory now claims
neither done nor working. The raw-array shell/cron veto stays uncapped.

src/shared/agent-hook-listener.test.ts

@@ -3192,9 +3192,36 @@ describe('shared agent-hook-listener', () => {
           { id: 'a2', type: 'subagent', status: 'running', agent_type: 'general-purpose' }
         ]
       })
-      // Why: veto only — a2's row materializes from its own events or the next
-      // lead Stop's fold; the stop must merely not retire the pane.
       expect(stopped?.payload.state).toBe('working')
+      // Why: the additive fold must TRACK a2 — otherwise its own later stop is
+      // start-less-suppressed and the pane sticks on working forever.
+      expect(stopped?.payload.subagents).toEqual([expect.objectContaining({ id: 'a2' })])
+
+      const drained = claudeEvent({ hook_event_name: 'SubagentStop', agent_id: 'a2' })
+      expect(drained?.payload.state).toBe('done')
+      expect(drained?.payload.subagents).toBeUndefined()
+    })
+
+    it('claims nothing from a no-lead removal whose agent inventory is truncated', () => {
+      claudeEvent({
+        hook_event_name: 'SubagentStart',
+        agent_id: 'a1',
+        agent_type: 'general-purpose'
+      })
+      // Why: 32 teammate rows fill the parser cap; the running subagent behind
+      // them is invisible, so the inventory can prove neither done nor working.
+      const cappedTasks = Array.from({ length: 32 }, (_, i) => ({
+        id: `t${i}`,
+        type: 'teammate',
+        status: 'running'
+      }))
+      cappedTasks.push({ id: 'hidden-live', type: 'subagent', status: 'running' })
+      const stopped = claudeEvent({
+        hook_event_name: 'SubagentStop',
+        agent_id: 'a1',
+        background_tasks: cappedTasks
+      })
+      expect(stopped).toBeNull()
     })
 
     it('keeps working when a no-lead drain leaves a live shell in the inventory', () => {

src/shared/agent-hook-listener.ts

@@ -2465,6 +2465,22 @@ function normalizeClaudeSubagentLifecycleEvent(
         stopClaudeSubagent(roster, agentId)
         removedRow = hadRow && !roster.has(agentId)
       }
+      // Why: the stop's inventory can list children this listener never saw start (post-restart);
+      // tracking them keeps their own later drains resolvable instead of start-less-suppressed.
+      // Additive only — a complete-inventory reap here would kill a just-parked teammate row
+      // before its TeammateIdle confirmation arrives.
+      const inventory = readClaudeBackgroundAgentTasks(hookPayload)
+      if (
+        inventory.present &&
+        (roster || inventory.tasks.some((task) => task.running && !task.teammate))
+      ) {
+        foldClaudeBackgroundTasksIntoRoster(
+          getOrCreateClaudeSubagentRoster(state, paneKey),
+          inventory.tasks,
+          Date.now(),
+          { inventoryComplete: false }
+        )
+      }
       // Why: a blocked child that dies without another tool event would pin its permission/question wait on the pane forever — nothing else references that agent again.
       clearClaudePendingWaitForAgent(state, paneKey, (waitingAgentId) => waitingAgentId === agentId)
     }
@@ -2594,16 +2610,22 @@ function buildClaudeChildDrivenStatusPayload(
     })
   }
   if (evidence.removedRow) {
-    // Why: the stop's own inventory can list work this listener never saw start (post-restart);
-    // a running non-teammate task or live shell/cron vetoes done. Teammate-typed entries prove
-    // nothing ("running" even while idle), and full folding here would reap a just-parked
-    // teammate row before its TeammateIdle confirmation arrives — veto only, no reconcile.
+    // Why: live shells/crons veto done (the raw-array check is uncapped). A truncated agent-task
+    // inventory is incomplete evidence — a running child past the parser cap would be invisible —
+    // so it claims neither done nor working. Running non-teammate tasks were already folded into
+    // the roster above and surface through the working branch.
+    if (hasActiveClaudeNonAgentBackgroundWork(hookPayload)) {
+      return buildClaudeStatusPayload(state, eventName, '', paneKey, hookPayload, {
+        stateName: 'working',
+        updateToolSnapshot: false
+      })
+    }
     const inventory = readClaudeBackgroundAgentTasks(hookPayload)
-    const inventoryShowsLiveWork =
-      inventory.tasks.some((task) => task.running && !task.teammate) ||
-      hasActiveClaudeNonAgentBackgroundWork(hookPayload)
+    if (inventory.present && inventory.truncated) {
+      return null
+    }
     return buildClaudeStatusPayload(state, eventName, '', paneKey, hookPayload, {
-      stateName: inventoryShowsLiveWork ? 'working' : 'done',
+      stateName: 'done',
       updateToolSnapshot: false
     })
   }