SAFETY-83: grade the refile at its boundary, and N=2 on its own

A floor exactly at the drain rate stays at P_PEAK (kills `lo >= rate`), and
part 4's N=2 check no longer shares its failure list with N=1.

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

goodwe_controller/test_safety83.py

@@ -25,6 +25,7 @@ import logging
 import os
 import sys
 import tempfile
+import types
 
 HERE = os.path.dirname(os.path.abspath(__file__))
 sys.path.insert(0, HERE)
@@ -34,9 +35,9 @@ logging.disable(logging.WARNING)
 import opt11_identity as rig                                   # noqa: E402
 import safety78_identity as s78                                # noqa: E402
 import safety79_identity as s79                                # noqa: E402
-from app.arbiter import P_MAINTENANCE, P_PEAK                  # noqa: E402
+from app.arbiter import Claim, P_MAINTENANCE, P_PEAK           # noqa: E402
 from app.main import Controller                                # noqa: E402
-from app.maintenance import CHARGE, DRAIN                      # noqa: E402
+from app.maintenance import CHARGE, DRAIN, MaintResult         # noqa: E402
 
 fails = []
 TOL = 1.0       # watts over the aim a banked quarter may show
@@ -201,18 +202,33 @@ for k, rows in _id.items():
                   and (not rate or r[1] == rate[0]))
         if not ok:
             _bad.append((k, r[0], r[1], r[6], pk))
+_bad1 = [b for b in _bad if b[0].startswith("n1")]
+_bad2 = [b for b in _bad if b[0].startswith("n2")]
 _more = {k: sum(map(s78.wanted_more, rows)) for k, rows in _id.items()}
 print(f"    cycles with the guard above the drain: {_more}; bad {_bad[:3]}")
 check("⭐ at N=1, on every cycle where the guard asks for more than the drain "
       "the peak claim is refiled at P_MAINTENANCE and the target is its floor; "
       "on every other cycle the peak claim stays at P_PEAK and the target is "
       "the drain rate",
-      not _bad and all(_more[k] > 50 for k in _id if k.startswith("n1")))
+      not _bad1 and all(_more[k] > 50 for k in _id if k.startswith("n1")))
 check("⭐ at N=2 the peak claim is never refiled (the SAFETY-78 floor does "
       "that job), and test_safety78.py part 5 holds N=2 to the digests of "
-      "release/1.0 35cdffe", not _bad)
+      "release/1.0 35cdffe", not _bad2)
 
 
+# The rule itself, at the boundary: a floor AT the drain rate changes nothing.
+_one = types.SimpleNamespace(inverters=[None])
+_edge = {}
+for lo in (1999.5, 2000.0, 2000.5):
+    cl = [Claim.set("maintenance", P_MAINTENANCE, 2000.0, DRAIN),
+          Claim.limit("peak", P_PEAK, lo=lo, reason="quarter peak")]
+    Controller._peak_over_drain(_one, cl, [MaintResult(DRAIN, True, 2000.0,
+                                                       False, [])])
+    _edge[lo] = cl[1].priority
+check("at the boundary: a floor at or below the 2000 W drain stays at P_PEAK, "
+      "a floor 0.5 W above it is refiled at P_MAINTENANCE",
+      _edge == {1999.5: P_PEAK, 2000.0: P_PEAK, 2000.5: P_MAINTENANCE})
+
 
 def store_hold():
     st = rig._Store()