fix: input steer says when a 1-step schedule leaves it nothing to do

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

samplers.py

@@ -939,6 +939,11 @@ class _InputSteer:
         if not self.enabled:
             return False
         where = self._where(args)
+        if where is not None and where[1] <= 1:
+            _log.note_once("FunPackSceneChain",
+                           f"{self.what}: a 1-step schedule has no step before the output "
+                           f"to carry an edit into, so it does nothing this run",
+                           key=f"input steer 1 step:{self.what}")
         return where is not None and where[0] >= where[1] - 1
 
     def gate_sigma(self, args, sigma):

tests/test_input_steer.py

@@ -191,3 +191,13 @@ def test_h3_a_size_change_is_said_not_silent(capsys):
     call(1, torch.randn(1, 2, 3, 4, 4))
     call(2, torch.randn(1, 2, 3, 4, 8))
     assert "latent size changed" in capsys.readouterr().out
+
+
+def test_h3_a_one_step_schedule_says_it_does_nothing(capsys):
+    import funpack_log
+    funpack_log.begin_run()
+    model = _Model()
+    _node(True)._build_tsr_wrapper(model, 0.5)
+    _euler(model.model_options["model_function_wrapper"], torch.randn(1, 2, 3, 4, 4),
+           schedule=torch.tensor([1.0, 0.0]))
+    assert "1-step schedule" in capsys.readouterr().out