updated /quit to use new slash command arch (#4259)

Co-authored-by: Abhi <abhipatel@google.com>

packages/cli/src/ui/commands/quitCommand.test.ts

@@ -0,0 +1,55 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { vi, describe, it, expect, beforeEach, afterEach } from 'vitest';
+import { quitCommand } from './quitCommand.js';
+import { createMockCommandContext } from '../../test-utils/mockCommandContext.js';
+import { formatDuration } from '../utils/formatters.js';
+
+vi.mock('../utils/formatters.js');
+
+describe('quitCommand', () => {
+  beforeEach(() => {
+    vi.useFakeTimers();
+    vi.setSystemTime(new Date('2025-01-01T01:00:00Z'));
+    vi.mocked(formatDuration).mockReturnValue('1h 0m 0s');
+  });
+
+  afterEach(() => {
+    vi.useRealTimers();
+    vi.clearAllMocks();
+  });
+
+  it('returns a QuitActionReturn object with the correct messages', () => {
+    const mockContext = createMockCommandContext({
+      session: {
+        stats: {
+          sessionStartTime: new Date('2025-01-01T00:00:00Z'),
+        },
+      },
+    });
+
+    if (!quitCommand.action) throw new Error('Action is not defined');
+    const result = quitCommand.action(mockContext, 'quit');
+
+    expect(formatDuration).toHaveBeenCalledWith(3600000); // 1 hour in ms
+    expect(result).toEqual({
+      type: 'quit',
+      messages: [
+        {
+          type: 'user',
+          text: '/quit',
+          id: expect.any(Number),
+        },
+        {
+          type: 'quit',
+          duration: '1h 0m 0s',
+          id: expect.any(Number),
+        },
+      ],
+    });
+  });
+});