feat: Add patchset history and diff support with cvsps integration

- Add cvsps package to Docker dependencies
- Implement patchset retrieval and diff endpoints in API
- Add _run_cvsps_command() helper for cvsps integration
- Enhance file history parsing with log message extraction
- Improve UI with enhanced styling and patchset functionality

cvs_proxy/test_cvs_client.py

@@ -143,7 +143,7 @@ class TestCVSClient(unittest.TestCase):
 
     @patch('cvs_proxy.cvs_client.subprocess.run')
     def test_get_file_history(self, mock_run):
-        """Test retrieving file history"""
+        """Test retrieving file history using cvs log"""
         mock_run.return_value = MagicMock(
             stdout='''
 revision 1.2
@@ -160,6 +160,16 @@ date: 2023/11/19 15:30:00;  author: testuser;  state: Exp;  lines: +10 -0
         self.assertEqual(len(history), 2)
         self.assertIn('revision', history[0])
         self.assertEqual(history[0]['revision'], '1.2')
+        self.assertEqual(history[0]['author'], 'testuser')
+        self.assertEqual(history[0]['date'], '2023/11/20 10:00:00')
+        self.assertEqual(history[0]['state'], 'Exp')
+        
+        # Verify the cvs log command was called correctly
+        mock_run.assert_called()
+        call_args = mock_run.call_args[0][0]
+        self.assertEqual(call_args[0], 'cvs')
+        self.assertIn('log', call_args)
+        self.assertIn('file.txt', call_args)
 
     @patch('cvs_proxy.cvs_client.subprocess.run')
     def test_get_file_content(self, mock_run):