debugger: Add stack frame multibuffer (#30395)

This PR adds the ability to expand a debugger stack trace into a multi
buffer and view each frame as it's own excerpt.

Release Notes:

- N/A

---------

Co-authored-by: Remco Smits <djsmits12@gmail.com>

crates/debugger_ui/src/debugger_ui.rs

@@ -7,14 +7,16 @@ use new_session_modal::NewSessionModal;
 use project::debugger::{self, breakpoint_store::SourceBreakpoint};
 use session::DebugSession;
 use settings::Settings;
+use stack_trace_view::StackTraceView;
 use util::maybe;
-use workspace::{ShutdownDebugAdapters, Workspace};
+use workspace::{ItemHandle, ShutdownDebugAdapters, Workspace};
 
 pub mod attach_modal;
 pub mod debugger_panel;
 mod new_session_modal;
 mod persistence;
 pub(crate) mod session;
+mod stack_trace_view;
 
 #[cfg(any(test, feature = "test-support"))]
 pub mod tests;
@@ -41,6 +43,7 @@ actions!(
         FocusModules,
         FocusLoadedSources,
         FocusTerminal,
+        ShowStackTrace,
     ]
 );
 
@@ -146,6 +149,38 @@ pub fn init(cx: &mut App) {
                         })
                     },
                 )
+                .register_action(
+                    |workspace: &mut Workspace, _: &ShowStackTrace, window, cx| {
+                        let Some(debug_panel) = workspace.panel::<DebugPanel>(cx) else {
+                            return;
+                        };
+
+                        if let Some(existing) = workspace.item_of_type::<StackTraceView>(cx) {
+                            let is_active = workspace
+                                .active_item(cx)
+                                .is_some_and(|item| item.item_id() == existing.item_id());
+                            workspace.activate_item(&existing, true, !is_active, window, cx);
+                        } else {
+                            let Some(active_session) = debug_panel.read(cx).active_session() else {
+                                return;
+                            };
+
+                            let project = workspace.project();
+
+                            let stack_trace_view = active_session.update(cx, |session, cx| {
+                                session.stack_trace_view(project, window, cx).clone()
+                            });
+
+                            workspace.add_item_to_active_pane(
+                                Box::new(stack_trace_view),
+                                None,
+                                true,
+                                window,
+                                cx,
+                            );
+                        }
+                    },
+                )
                 .register_action(|workspace: &mut Workspace, _: &Start, window, cx| {
                     NewSessionModal::show(workspace, window, cx);
                 });