test(annotations): capture the details panel after it has loaded

"Tag opens the dialog without selecting the card" read the panel while it
still said "Loading file details…", then compared it with the same card's
finished details. On a slow WebKit runner the read raced the load.

tests/browser/workspace-tagging.spec.mjs

@@ -340,6 +340,9 @@ test('Tag opens the dialog without selecting the card', async ({ page }) => {
     const panel = page.getByRole('complementary', { name: 'Selected image details', exact: true });
     await page.goto(images);
     await expect(card(page, FIRST)).toHaveClass(/\bselected\b/);
+    // Capture the panel once it shows the first card's details, not while it is still reading them.
+    await expect(panel.getByRole('heading', { level: 2 })).toBeVisible();
+    await expect(panel).not.toContainText('Loading file details');
     const before = await panel.innerText();
     await openTag(page, SECOND, { goto: false });
     await page.keyboard.press('Escape');