CI-02 probe F: the ORIGINAL gate, unchanged, on the same unmergeable PR

goodwe_controller/test_maintenance.py

@@ -3,6 +3,13 @@
 Walks a whole cycle in simulated time, which is the test the YAML version never
 had - and it is exactly the phase transitions that a real cycle takes ten hours
 to exercise once a month.
+
+⚠️ MUTATING THE MODULE THIS FILE GRADES? PURGE `__pycache__` FIRST - or run
+`tools/mutation_run.sh`, which does. `python3 -B` alone does NOT save you: it
+stops bytecode being WRITTEN, not a stale one being READ, and a size-preserving
+edit reverted inside one second is invisible to CPython's staleness test. That
+is TEST-15, and it has already turned one live mutation into a false survivor.
+Read MUTATION.md before you report a survivor.
 """
 
 import sys