feat(cli): improve CTRL+O experience for both standard and alternate screen buffer (ASB) modes (#19010)

Co-authored-by: jacob314 <jacob314@gmail.com>

packages/cli/src/ui/components/ToastDisplay.test.tsx

@@ -35,12 +35,22 @@ describe('ToastDisplay', () => {
       buffer: { text: '' } as TextBuffer,
       history: [] as HistoryItem[],
       queueErrorMessage: null,
+      showIsExpandableHint: false,
     };
 
     it('returns false for default state', () => {
       expect(shouldShowToast(baseState as UIState)).toBe(false);
     });
 
+    it('returns true when showIsExpandableHint is true', () => {
+      expect(
+        shouldShowToast({
+          ...baseState,
+          showIsExpandableHint: true,
+        } as UIState),
+      ).toBe(true);
+    });
+
     it('returns true when ctrlCPressedOnce is true', () => {
       expect(
         shouldShowToast({ ...baseState, ctrlCPressedOnce: true } as UIState),
@@ -170,4 +180,22 @@ describe('ToastDisplay', () => {
     await waitUntilReady();
     expect(lastFrame()).toMatchSnapshot();
   });
+
+  it('renders expansion hint when showIsExpandableHint is true', async () => {
+    const { lastFrame, waitUntilReady } = renderToastDisplay({
+      showIsExpandableHint: true,
+      constrainHeight: true,
+    });
+    await waitUntilReady();
+    expect(lastFrame()).toContain('Press Ctrl+O to show more lines');
+  });
+
+  it('renders collapse hint when showIsExpandableHint is true and constrainHeight is false', async () => {
+    const { lastFrame, waitUntilReady } = renderToastDisplay({
+      showIsExpandableHint: true,
+      constrainHeight: false,
+    });
+    await waitUntilReady();
+    expect(lastFrame()).toContain('Press Ctrl+O to collapse lines');
+  });
 });