优化雅可比矩阵计算；端口转发情况下仿真结果传输方式优化

tests/test_native_codegen.py

@@ -88,10 +88,19 @@ class NativeExecutionTests(unittest.TestCase):
             data = execute_native(self.build, config, .02, run_dir=self.root / method)
             self.assertTrue(data["success"])
             self.assertEqual(data["simulatedUntil"], .1)
+            self.assertEqual(data["jacobianMode"], "dense-difference" if method == "BDF" else "not-used")
+            self.assertEqual(data["jacobianRhsCalls"], 0)  # Compact model has no grouping benefit.
             self.assertLessEqual(data["maxAcceptedStep"], config.max_step+1e-14)
             self.assertEqual(set(data["series"]), {"time", *(v.key for v in self.program.variables)})
             self.assertTrue(all(np.isfinite(v).all() for v in map(np.asarray, data["series"].values())))
 
+    def test_retired_jacobian_selector_is_rejected(self):
+        for policy in ("dense", "auto", "verify"):
+            with self.subTest(policy=policy):
+                result = subprocess.run([str(self.build.executable), "--jacobian", policy],
+                                        cwd=self.root, capture_output=True, text=True, timeout=10)
+                self.assertEqual(result.returncode, 64)
+
     def test_cancellation_returns_partial_accepted_state(self):
         config = replace(simulation_config(self.document.simulation), max_step=1e-6)
         tracker = SolverActivityTracker()