fix(e2e): scope remaining getByText to main element

The 'Cluster Score' text matcher was still searching the entire page
instead of being scoped to the main content area. This could cause
false positives if the same text appears in the sidebar.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

e2e/polaris.spec.ts

@@ -18,7 +18,7 @@ test.describe('Polaris plugin smoke tests', () => {
     ).toBeVisible();
 
     // "Cluster Score" section exists with a percentage
-    await expect(page.getByText('Cluster Score')).toBeVisible();
+    await expect(page.locator('main').getByText('Cluster Score')).toBeVisible();
     await expect(page.locator('main').getByText(/%/).first()).toBeVisible();
   });