Model Swap Mid-convo provides little feedback & seems to silently override choice

### Short summary

Model Swap Mid-convo provides little feedback & seems to silently override choice

### Affected version or release

v1.0.24

### Installation context

_No response_

### What happened?

I often find I am pretty frustrated by the model selection UI and lack of feedback when changing model mid-convo.

I will want to swap a model as I realize the task isn't suitable or that I am running into compaction too quickly. Or sometimes get rate limited etc. As a result, I often want to swap the model. If you do this while the agent is reasoning, my selection is seemingly silently swapped back & it takes pausing, interrupting the convo, and like waiting 5 seconds (I probably am exaggerating) for my choice to get reflected. If I don't do this, it seems like my choice is never reflected & there isn't a clear signal on why/if I just need to wait etc.

I think mostly this makes sense but like having some indication that the change will go into effect would improve the experience / since it's unclear if there is an error or something else from my pov

### Steps to reproduce

1. Start convo
2. Swap model
3. Model choice isn't clearly pending & the model modal swaps back to the previous one.

### Expected behavior

I'd expect either my choice to be reflected OR a clear indication that my change is pending before the swap occurs

### Additional context

Payload không nêu tên tệp hay bài kiểm thử nào. Hãy bắt đầu bằng cách xác định UI chọn model của ứng dụng desktop và tái hiện việc đổi model trong khi agent đang suy luận; theo dõi nơi lựa chọn được cập nhật và xác minh rằng model đã chọn vẫn hiển thị hoặc hiển thị trạng thái đang chờ một cách rõ ràng.

Do mô hình lập chỉ mục viết ra từ nội dung của issue.