test(settings): guard the unsaved-changes bar after a save off the sections

Review follow-up (Codex): Save marks the form pristine after an async
store write, also on Backup, Reset or search, where no form section is
rendered. The OnPush page re-renders anyway because pristine and valid
read the form's state signals; the new test checks that on the Backup
page without forcing a render (it waits for the scheduled one).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

apps/web/src/app/settings/settings.component.form.spec.ts

@@ -354,6 +354,29 @@ describe('SettingsComponent form', () => {
             expect(unsavedBar()).toBeNull();
         });
 
+        // The page owns the bar and is OnPush, and Save marks the form
+        // pristine after an async store write, also on a page without a form
+        // section. `pristine` and `valid` read the form's state signals, so
+        // the page re-renders without a form subscription; no forced render
+        // here, so a regression shows.
+        it('hides after a save on a page without a form section', async () => {
+            settingsStore.updateSettings.mockResolvedValue(undefined);
+            setSettingsSection('backup');
+            fixture.autoDetectChanges();
+            component.settingsForm.get('theme')?.setValue(Theme.DarkTheme);
+            component.settingsForm.markAsDirty();
+            await fixture.whenStable();
+            expect(unsavedBar()).not.toBeNull();
+
+            component.onSubmit();
+            await fixture.whenStable();
+            // The render the form event scheduled runs in the next macrotask.
+            await new Promise((resolve) => setTimeout(resolve));
+
+            expect(component.settingsForm.pristine).toBe(true);
+            expect(unsavedBar()).toBeNull();
+        });
+
         it('discard reverts a staged cover size (regression: eager persist made it stick)', () => {
             const largeCoverButton = (
                 fixture.nativeElement as HTMLElement