test(episodes): bind mixed control to one segment

Author: stacknil

tests/test_episode_candidate.py

@@ -16,6 +16,7 @@
     validate_oracle,
 )
 from scripts.episode_candidate_core import (  # noqa: E402
+    activity_segments,
     enumerate_candidate_windows,
     parse_timestamp,
     select_window_separated_candidates,
@@ -265,6 +266,7 @@ def test_v2_mixed_contrasts_reject_unchanged_selection_and_keep_boundaries(
 
         admission = materialize_core_contrast_admission(events, selected, 5)
 
+        self.assertEqual(len(activity_segments(events, 600)), 1)
         self.assertEqual(
             [candidate.candidate_id for candidate in selected],
             [