"Pending message" doesn't clear on correct timming

Describe the bug

Found an issue where my Pending message is already consumed and the agent is thinking on it (I can read the thinking) but the message still has "(pending)" appended to it, thus misleading me.

Affected version

GitHub Copilot CLI 1.0.75.

Steps to reproduce the behavior

1. Ask tasks that need thinking while on medium or high thinking
2. Add additional prompts while it is still processing (you message is now pending)
3. Check the "Pending message" is appended
4. when the agent start thinking about your message, check the "Pending message" text is still present, although the message has already been delivered.

Expected behavior

The "pending message" should clear before the agent starts thinking about the message, becaue by now it no longer is pending but was already delivered.

Additional context

No response

Tái hiện điều này trong GitHub Copilot CLI 1.0.75 bằng cách gửi một prompt đang chờ trong hàng đợi trong lúc suy nghĩ ở mức trung bình hoặc cao, sau đó quan sát khi agent bắt đầu xử lý prompt đó. Theo dõi phần hiển thị tin nhắn đang chờ trong quá trình chuyển từ queued sang delivered, và coi issue là hoàn tất khi dòng chữ “(pending)” biến mất trước khi agent bắt đầu suy nghĩ về tin nhắn.