fix: restore reliable authenticated live recognition

recognization/code/test_live.py

@@ -276,6 +276,36 @@ class TagPassIntegrationTests(unittest.TestCase):
         self.assertNotIn("price_tag", result["tracks"][0])
         engine.shutdown()
 
+    def test_a_panned_shelf_reusing_the_screen_row_is_planned(self):
+        """The same screen row on a shelf that has moved is a new rail."""
+        session, engine, _ = self.make_tagged_session()
+        session._tags.settings.pass_interval_frames = 0
+        session._tags.settings.settle_observations = 1
+        session._tags.settings.settle_passes = 1
+
+        class Panned:
+            def __init__(self):
+                self.calls = 0
+
+            def register(self, image):
+                self.calls += 1
+                # Content moved up 400 px, so the frame origin moves down the shelf.
+                return (0.0, -400.0) if self.calls == 2 else (0.0, 0.0)
+
+        session._shift_map = Panned()
+        process(session, 1)
+        time.sleep(0.05)
+        before = session._tags.stats()["passes_run"]
+        self.assertGreaterEqual(before, 1)
+        process(session, 2)
+        time.sleep(0.1)
+        self.assertGreaterEqual(session._frame_origin[1], 400.0)
+        self.assertGreater(
+            session._tags.stats()["passes_run"], before,
+            "a shelf 400 px away reuses screen row 0 and must be read again",
+        )
+        engine.shutdown()
+
 
 class FramePipelineTests(unittest.TestCase):
     def test_latest_frame_wins_and_drops_are_counted(self):