Fix status bar not updating when workspace first opens

Fixes #1729

The tabBarTabIdSubject was a PassthroughSubject, which doesn't replay
its current value to new subscribers. When the workspace opens, the
initial tab selection is sent before the status bar view subscribes,
so it never receives the initial value.

Changed to CurrentValueSubject so late subscribers (like the status
bar) immediately receive the current tab selection on subscription.

Author: William-Laverty

CodeEdit/Features/Editor/Models/EditorManager.swift

@@ -29,8 +29,9 @@ class EditorManager: ObservableObject {
     /// History of last-used editors.
     var activeEditorHistory: Deque<() -> Editor?> = []
 
-    /// notify listeners whenever tab selection changes on the active editor.
-    var tabBarTabIdSubject = PassthroughSubject<Editor.Tab?, Never>()
+    /// Notify listeners whenever tab selection changes on the active editor.
+    /// Uses `CurrentValueSubject` so late subscribers (e.g. status bar) receive the current value immediately.
+    var tabBarTabIdSubject = CurrentValueSubject<Editor.Tab?, Never>(nil)
     var cancellable: AnyCancellable?
 
     // This caching mechanism is a temporary solution and is not optimized