fix web review validation and clipboard tests

apps/web/src/features/workbench/channels/CustomLinkChannel.test.ts

@@ -1,6 +1,6 @@
 import '@testing-library/jest-dom/vitest';
 import { cleanup, fireEvent, render, screen, waitFor } from '@testing-library/svelte';
-import { afterEach, describe, expect, it } from 'vitest';
+import { afterEach, describe, expect, it, vi } from 'vitest';
 import CustomLinkChannel from './CustomLinkChannel.svelte';
 
 const channel = {
@@ -14,6 +14,13 @@ const channel = {
 };
 const originalClipboard = Object.getOwnPropertyDescriptor(navigator, 'clipboard');
 
+function setClipboard(writeText: Clipboard['writeText']) {
+  Object.defineProperty(navigator, 'clipboard', {
+    configurable: true,
+    value: { writeText } as Clipboard,
+  });
+}
+
 afterEach(() => {
   cleanup();
   if (originalClipboard) {
@@ -24,6 +31,33 @@ afterEach(() => {
 });
 
 describe('CustomLinkChannel', () => {
+  it('shows copy success only after clipboard writing resolves', async () => {
+    let resolveWrite: (() => void) | undefined;
+    const writeText = vi.fn(
+      () =>
+        new Promise<void>((resolve) => {
+          resolveWrite = resolve;
+        }),
+    );
+    setClipboard(writeText);
+    render(CustomLinkChannel, { props: { channel } });
+
+    await fireEvent.click(screen.getByRole('button', { name: 'Copy URL' }));
+
+    expect(screen.queryByText('URL copied.')).not.toBeInTheDocument();
+    resolveWrite?.();
+    await waitFor(() => expect(screen.getByText('URL copied.')).toBeInTheDocument());
+  });
+
+  it('reports a copy failure when clipboard writing rejects', async () => {
+    setClipboard(vi.fn().mockRejectedValue(new Error('Permission denied')));
+    render(CustomLinkChannel, { props: { channel } });
+
+    await fireEvent.click(screen.getByRole('button', { name: 'Copy URL' }));
+
+    await waitFor(() => expect(screen.getByText('Unable to copy URL.')).toBeInTheDocument());
+  });
+
   it('reports unavailable clipboard access without showing URL copied', async () => {
     Reflect.deleteProperty(navigator, 'clipboard');
     render(CustomLinkChannel, { props: { channel } });