debugger: Remember pane layout from previous debugger session (#28692)

This PR makes a debugger's pane layout persistent across session's that
use the same debug adapter.

Release Notes:

- N/A

---------

Co-authored-by: Piotr Osiewicz <24362066+osiewicz@users.noreply.github.com>
Co-authored-by: Cole Miller <m@cole-miller.net>

crates/debugger_ui/src/tests.rs

@@ -68,6 +68,7 @@ pub async fn init_test_workspace(
     workspace_handle
 }
 
+#[track_caller]
 pub fn active_debug_session_panel(
     workspace: WindowHandle<Workspace>,
     cx: &mut TestAppContext,