It would be great if New chat used the sidebar's project scope

[AI091]

It would be great if New chat respected the sidebar's project scope.

When I scope the sidebar to a project, I've already said which project I'm working in. But New chat (the button or Ctrl+Shift+O) still opens the "New thread in…" picker, with the project of whatever thread I'm viewing highlighted. That's often not the project I just scoped to. If I accept that default, the new chat lands in a project the filtered list hides.

What I'd love: while the sidebar is scoped, New chat creates the chat in that project directly. Unscoped, nothing changes.

Before

After

I put together a small reference implementation in #14165 in case it's useful. Happy for it to be reshaped or done differently.

[juliusmarminge]

Closing as a duplicate of #17988, which tracks the same request. Please follow along there.