feat: extend stall timeout and remove sample cap

tests/test_generic_system_xml_simulation.py

@@ -475,6 +475,20 @@ class GenericSystemXmlSimulationTests(unittest.TestCase):
             "port_a",
         )
 
+    def test_raw_system_xml_serializes_more_than_legacy_sample_limit(self) -> None:
+        project = chain_project()
+        project.simulation.step = 0.0000005
+        xml = build_reactflow_system_xml(project)
+
+        response = asyncio.run(simulate_system_xml(xml_request(xml)))
+        round_tripped = json.loads(json.dumps(response))
+
+        self.assertTrue(round_tripped["success"])
+        self.assertEqual(round_tripped["diagnostics"]["sampleCount"], 20001)
+        self.assertEqual(len(round_tripped["series"]["time"]), 20001)
+        self.assertEqual(round_tripped["series"]["time"][0], 0.0)
+        self.assertEqual(round_tripped["series"]["time"][-1], 0.01)
+
     def test_streaming_endpoint_events_have_monotonic_progress_and_result(self) -> None:
         project = chain_project()
         xml = build_reactflow_system_xml(project)

tests/test_simulation_safety.py

@@ -107,15 +107,22 @@ class SimulationSampleTimeSafetyTests(unittest.TestCase):
             [1.0, 1.25],
         )
 
-    def test_exact_point_limit_is_allowed(self) -> None:
+    def test_grid_can_exceed_the_legacy_point_limit(self) -> None:
         times = simulation_sample_times(
-            SolveIVPConfig(t_start=0.0, t_stop=1.0),
+            SolveIVPConfig(t_start=0.0, t_stop=5.0),
             0.0001,
         )
 
-        self.assertEqual(len(times), 10001)
+        self.assertEqual(len(times), 50001)
         self.assertEqual(times[0], 0.0)
-        self.assertEqual(times[-1], 1.0)
+        self.assertEqual(times[-1], 5.0)
+
+    def test_system_xml_accepts_more_than_the_legacy_point_limit(self) -> None:
+        report = validate_system_xml_document(
+            _system_xml(t_start="0", t_stop="5", sample_step="0.0001")
+        )
+
+        self.assertTrue(report.valid, report.issues)
 
     def test_tiny_step_is_rejected_before_an_oversized_grid_is_allocated(self) -> None:
         with self.assertRaises(SimulationSampleTimeError) as caught:
@@ -124,7 +131,10 @@ class SimulationSampleTimeSafetyTests(unittest.TestCase):
                 1.0e-300,
             )
 
-        self.assertEqual(caught.exception.code, "SIMULATION_SAMPLE_COUNT_EXCEEDED")
+        self.assertEqual(
+            caught.exception.code,
+            "SIMULATION_SAMPLE_COUNT_UNREPRESENTABLE",
+        )
 
     def test_non_finite_derived_duration_has_a_stable_error(self) -> None:
         with self.assertRaises(SimulationSampleTimeError) as caught:
@@ -153,7 +163,7 @@ class SimulationSampleTimeSafetyTests(unittest.TestCase):
         cases = (
             (
                 _system_xml(t_start="0", t_stop="1", sample_step="1e-300"),
-                "SIMULATION_SAMPLE_COUNT_EXCEEDED",
+                "SIMULATION_SAMPLE_COUNT_UNREPRESENTABLE",
             ),
             (
                 _system_xml(