Mark all read on an OPML subscription

Marking the subscription read did nothing: its own row holds no entries.
read-all now resolves the feeds grouped under the id -- via
subscriptions(), so a child promoted to config is included -- and marks
those. Button sits before Unsubscribe, where every other feed keeps it.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AdXho5tTkjFLeUXKbEjKBh

tests/ui/app.spec.js

@@ -189,3 +189,21 @@ test('an OPML subscription is a collapsible folder', async ({ page }) => {
   await page.locator('.feed', { hasText: 'Test Subscriptions' }).first().click();
   await expect(page.locator('.childrow')).toHaveCount(1);
 });
+
+test('marking an OPML subscription read covers the feeds inside it', async ({ page }) => {
+  await page.evaluate(() =>
+    fetch('/api/fetch', {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({ feed: 'test-subscriptions', force: true }),
+    }));
+
+  // The folder's own row has no entries, so anything it marks read came from its child.
+  const folder = page.locator('.feed', { hasText: 'Test Subscriptions' }).first();
+  await expect(folder).toBeVisible({ timeout: 20_000 });
+  await expect(folder.locator('.badge')).not.toHaveText('0');
+  await folder.click();
+
+  await page.locator('#content .acts button', { hasText: 'Mark all read' }).click();
+  await expect(folder.locator('.badge')).toHaveText('0');
+});