SAFETY-97: test the centred stale-path refusal (mutant S10 survived)

At a 5 s meter a register frozen at rest on B trips the stale gate before
the 12-cycle evidence; its refusal must be centred on B's idle reading,
or the site stops and re-trips instead of refusing B.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019DBUfvndgHwaV339Fvd2gr

goodwe_controller/test_safety97.py

@@ -124,6 +124,22 @@ print(f"    B's register frozen at rest from 300 s, asked at 600 s: 0 W at "
       f"{park}")
 check("a register frozen at rest on B is caught as on A (within 36 s of "
       "the ask)", park is not None and park - 600.0 <= 36.0)
+# At a 5 s meter the stale trip comes first: its refusal is centred too.
+saved = dict(rig.OFFSET)
+rig.OFFSET["b"] = -110.0
+try:
+    r = rig.run(2, lambda t: 2500.0 if t >= 600 else 0.0, 760.0, tick=5.0,
+                publish_s=1.0, dither=True,
+                freeze_at=lambda u: 300.0 if u == "b" else None)
+finally:
+    rig.OFFSET.clear()
+    rig.OFFSET.update(saved)
+st = [t for t, u in r["stale"] if u == "inverter-b"]
+ref = [t for t, u in r["refused"] if u == "inverter-b"]
+print(f"    the same at a 5 s meter, B idle -110 W: stale {st}, refused {ref}")
+check("...and at a 5 s meter the stale trip on B's held -110 W is a refusal "
+      "of B (one trip), not a repeating site stop",
+      len(st) == 1 and ref == st)
 
 # ============================================================================ #
 print("\n2. a healthy B with its offset is never refused or flagged")