Implement selection change handling in ViewportHost, triggering refresh of paths, markers, and model instances, and update related integration tests.

tests/unit/path-inspector.integration.test.tsx

@@ -9,6 +9,7 @@ const { MockViewportHost, viewportHostInstances } = vi.hoisted(() => {
     updateSimulation: ReturnType<typeof vi.fn>;
     updateAssets: ReturnType<typeof vi.fn>;
     updateDocument: ReturnType<typeof vi.fn>;
+    updateSelection: ReturnType<typeof vi.fn>;
     setPanelId: ReturnType<typeof vi.fn>;
     setRenderEnabled: ReturnType<typeof vi.fn>;
     setViewMode: ReturnType<typeof vi.fn>;
@@ -38,6 +39,7 @@ const { MockViewportHost, viewportHostInstances } = vi.hoisted(() => {
     updateSimulation = vi.fn();
     updateAssets = vi.fn();
     updateDocument = vi.fn();
+    updateSelection = vi.fn();
     setPanelId = vi.fn();
     setRenderEnabled = vi.fn();
     setViewMode = vi.fn();