After moving chat to editor, the chat view agent picker is stale

[eleanorjboyd]

Testing #274957

ok so I was going through a lot of things and ended up in this state. Here is what I think were the steps to get there:

1. have the custom agent mode open
2. click to open in editor
3. (this causes a new window to open and the chat panel goes to a blank new chat I think in "agent" mode)
4. exit out of the chat mode in the editor (I ended up having to select "save and exit" since I had some changes)
5. now the chat panel has the custom agent mode (this is an update because the chat panel had a blank chat with I think "agent" mode)
6. I cannot switch modes in the UI (see video)

2025-11-04_09-16-10.mp4

[aeschli]

As soon as a chat is opened in the editor, changes in the chat view seem to be stale. If fact they make changes in the chat editor:

20251105-1320-21.2910030.mp4