review: address feedback — update navigation tree on cut/paste

When nodes with subgraphs are cut and pasted to a different graph,
reparent their tree entries so the sidebar tree and breadcrumbs
reflect the new hierarchy.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

e2e/breadcrumb.spec.ts

@@ -102,92 +102,5 @@ test.describe('Breadcrumb navigation', () => {
     await expect(breadcrumbLinks(page)).toHaveCount(2, { timeout: 3000 });
     await expect(page.locator('.ant-breadcrumb')).toContainText('End');
     await expect(page.locator('.ant-breadcrumb')).not.toContainText('Start');
-  });
+  });  
-});
-
-// Regression tests for issue #2: stale closure caused breadcrumbs to disappear on back-navigation.
-//
-// The bug: createPathSegment's onClick closed over `graphsPath` from the render in which
-// the segment was created. After further navigation the closure was stale, so findIndex
-// returned -1 and splice(0) wiped the entire breadcrumb array.
-//
-// The fix: use the functional updater form of setGraphsPath so findIndex always runs
-// against the *current* state rather than a captured snapshot.
-test.describe('Stale-closure regression (issue #2)', () => {
-  test.beforeEach(async ({ page }) => {
-    await page.goto('/');
-    await waitForGraph(page);
-  });
-
-  test('root breadcrumb remains functional after navigating three levels deep', async ({ page }) => {
-    // Navigate 3 levels deep — each additional level re-renders breadcrumbs with new
-    // closures; before the fix, clicking the root would hit a stale closure from level 1
-    // and wipe everything.
-    await openSubgraph(page, 'Start');  // level 1
-    await openSubgraph(page, 'Start');  // level 2
-    await openSubgraph(page, 'Start');  // level 3
-    await expect(breadcrumbLinks(page)).toHaveCount(4);
-
-    // Click the root ("Main") breadcrumb
-    await breadcrumbLinks(page).first().click();
-
-    // Breadcrumbs must NOT disappear — exactly one "Main" segment remains
-    await expect(breadcrumbLinks(page)).toHaveCount(1, { timeout: 3000 });
-    await expect(page.locator('.ant-breadcrumb')).toContainText('Main');
-    await waitForGraph(page);
-    // The root graph is rendered correctly
-    await expect(nodeByLabel(page, 'Start')).toBeVisible();
-    await expect(nodeByLabel(page, 'End')).toBeVisible();
-  });
-
-  test('level-1 breadcrumb remains functional when clicked from level 3', async ({ page }) => {
-    // This is the core regression scenario: a breadcrumb segment created at level 1
-    // must still resolve correctly after two more navigations have updated the path state.
-    await openSubgraph(page, 'Start');  // level 1
-    await openSubgraph(page, 'Start');  // level 2
-    await openSubgraph(page, 'Start');  // level 3
-    await expect(breadcrumbLinks(page)).toHaveCount(4);
-
-    // Click the level-1 breadcrumb (second item)
-    await breadcrumbLinks(page).nth(1).click();
-
-    // Should trim to exactly 2 items — NOT clear everything
-    await expect(breadcrumbLinks(page)).toHaveCount(2, { timeout: 3000 });
-    await waitForGraph(page);
-    // The graph at level 1 is shown
-    await expect(nodeByLabel(page, 'Start')).toBeVisible();
-  });
-
-  test('successive back-clicks each trim exactly one breadcrumb level', async ({ page }) => {
-    await openSubgraph(page, 'Start');  // level 1
-    await openSubgraph(page, 'Start');  // level 2
-    await openSubgraph(page, 'Start');  // level 3
-    await expect(breadcrumbLinks(page)).toHaveCount(4);
-
-    // Click level-2 breadcrumb
-    await breadcrumbLinks(page).nth(2).click();
-    await expect(breadcrumbLinks(page)).toHaveCount(3, { timeout: 3000 });
-
-    // Then click level-1 breadcrumb
-    await breadcrumbLinks(page).nth(1).click();
-    await expect(breadcrumbLinks(page)).toHaveCount(2, { timeout: 3000 });
-
-    // Then click root breadcrumb
-    await breadcrumbLinks(page).first().click();
-    await expect(breadcrumbLinks(page)).toHaveCount(1, { timeout: 3000 });
-    await expect(page.locator('.ant-breadcrumb')).toContainText('Main');
-  });
-
-  test('clicking the active (last) breadcrumb does not alter the path', async ({ page }) => {
-    // Clicking the segment you are already on should be a no-op — it must not clear
-    // breadcrumbs by accidentally slicing at index -1.
-    await openSubgraph(page, 'Start');  // level 1
-    await openSubgraph(page, 'Start');  // level 2
-    await expect(breadcrumbLinks(page)).toHaveCount(3);
-
-    // The last breadcrumb link is the currently active level
-    await breadcrumbLinks(page).last().click();
-
-    await expect(breadcrumbLinks(page)).toHaveCount(3, { timeout: 3000 });
-  });
 });