fix: Auto-complete tasks when agents finish successfully

The orchestrator's agent:stopped listener only called scheduleDispatch(),
never marking the agent's assigned task as completed. Tasks stayed
in_progress forever after their agent finished.

Now handleAgentStopped() calls dispatchManager.completeTask() before
scheduling new dispatches, respecting requiresApproval and skipping
manual (user_requested) stops.

apps/server/execution/orchestrator.ts

@@ -59,8 +59,12 @@ export class ExecutionOrchestrator {
     // Kick off dispatch when phases are queued (e.g. user clicks Execute)
     this.eventBus.on<PhaseQueuedEvent>('phase:queued', () => this.scheduleDispatch());
 
-    // Re-dispatch queued tasks when an agent finishes and frees a slot
+    // Auto-complete task + re-dispatch when an agent finishes
-    this.eventBus.on<AgentStoppedEvent>('agent:stopped', () => this.scheduleDispatch());
+    this.eventBus.on<AgentStoppedEvent>('agent:stopped', (event) => {
+      this.handleAgentStopped(event).catch((err) => {
+        log.error({ err: err instanceof Error ? err.message : String(err) }, 'error handling agent:stopped');
+      });
+    });
 
     log.info('execution orchestrator started');
   }
@@ -83,6 +87,25 @@ export class ExecutionOrchestrator {
     );
   }
 
+  private async handleAgentStopped(event: AgentStoppedEvent): Promise<void> {
+    const { taskId, reason, agentId } = event.payload;
+
+    // Auto-complete task for successful agent completions, not manual stops
+    if (taskId && reason !== 'user_requested') {
+      try {
+        await this.dispatchManager.completeTask(taskId, agentId);
+        log.info({ taskId, agentId, reason }, 'task auto-completed on agent stop');
+      } catch (err) {
+        log.warn(
+          { taskId, agentId, reason, err: err instanceof Error ? err.message : String(err) },
+          'failed to auto-complete task on agent stop',
+        );
+      }
+    }
+
+    this.scheduleDispatch();
+  }
+
   private async runDispatchCycle(): Promise<void> {
     this.dispatchRunning = true;
     try {