feat(silo): replace modal new-item dialog with MDI pre-document tab

Update silo submodule to include the new pre-document tab for item
creation.  Silo_New now opens an MDI tab instead of a blocking modal
dialog, allowing multiple items to be prepared in parallel.

src/Gui/MainWindow.cpp

@@ -105,6 +105,8 @@
 #include "SelectionView.h"
 #include "SplashScreen.h"
 #include "StatusBarLabel.h"
+#include "BreadcrumbToolBar.h"
+#include "EditingContext.h"
 #include "ToolBarManager.h"
 #include "ToolBoxManager.h"
 #include "Tree.h"
@@ -305,6 +307,7 @@ struct MainWindowP
     QLabel* actionLabel;
     InputHintWidget* hintLabel;
     QLabel* rightSideLabel;
+    BreadcrumbToolBar* breadcrumbBar = nullptr;
     QTimer* actionTimer;
     QTimer* statusTimer;
     QTimer* activityTimer;
@@ -489,6 +492,20 @@ MainWindow::MainWindow(QWidget* parent, Qt::WindowFlags f)
 #endif
     connect(d->mdiArea, &QMdiArea::subWindowActivated, this, &MainWindow::onWindowActivated);
 
+    // Breadcrumb toolbar for editing context display
+    d->breadcrumbBar = new BreadcrumbToolBar(this);
+    addToolBar(Qt::TopToolBarArea, d->breadcrumbBar);
+    insertToolBarBreak(d->breadcrumbBar);
+
+    // Initialize the editing context resolver and connect to breadcrumb
+    auto* ctxResolver = EditingContextResolver::instance();
+    connect(
+        ctxResolver,
+        &EditingContextResolver::contextChanged,
+        d->breadcrumbBar,
+        &BreadcrumbToolBar::updateContext
+    );
+
     setupDockWindows();
 
     // accept drops on the window, get handled in dropEvent, dragEnterEvent