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/debugger_ui.rs

@@ -13,6 +13,7 @@ use workspace::{ShutdownDebugAdapters, Workspace};
 pub mod attach_modal;
 pub mod debugger_panel;
 mod new_session_modal;
+mod persistence;
 pub(crate) mod session;
 
 #[cfg(test)]