Main agent is not receiving work completed notifications from sub agent

[CezaryKlus]

Describe the bug

The main orchestration agent is not receiving notifications about the work done from sub agents. Hence the whole orchestration pattern does not work in CLI.

Affected version

GitHub Copilot CLI 1.0.34

Steps to reproduce the behavior

• Create orchestration and sub agents e.g.

---
name: Work Item
description: Orchestrator for work item implementation. Delegates each phase to specialized subagents, uses notes files for handoff.
agents: ['WI Doc Reader', 'WI Planner', 'WI Implementer', 'WI Impact Analyser', 'WI Functional Tester', 'WI Documenter', 'WI PR Creator']
argument-hint: "Work Item ID (e.g. 12345) and short description of the work item"
---

• Observe the main agent is not progressing due to the missed sub agent notifications

Expected behavior

Orchestration pattern works

Additional context

• Ubuntu Linux
• Related issue that should be reopened: v1.0.5 regression: background agent completion notifications not delivered to model #2051