SAFETY-125: a grid charge counts a late meter reading's seconds; the guard row says "over" when it is

A meter reading late near a quarter's end left seconds the projection did
not count (SAFETY-99), and charge_headroom_w() read them as room: the cheap
run (and price trading, and the N=2 maintenance charge) went back to full
power in the quarter's last seconds and the quarter could land over a banked
month peak or the cap. peakguard.charge_room_w() counts those seconds at the
held reading for the charge only; the guard's floor is unchanged.

The guard row said "idle, heading for 5 814 W, under this month's 5 413 W
peak". Over the limit at the current rate the row and the month-peak line
now say so, and that the grid charge is cut back.

Version 0.19.2, CHANGELOG, DECISIONS. test_safety125.py new; the lag pins
in test_price_run_fixes.py and test_opt20.py and the AST pin in
test_arbitrage.py follow the change (see the pull request).

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

goodwe_controller/app/homeview.py

@@ -963,7 +963,8 @@ def month_peak(c, now):
         ceiling = pg.ceiling_w or limit_w
     out["line"] = line_period(out["period_w"], ceiling, c.shadow,
                               unmeasured=getattr(c, "peak_unmeasured_s", 0.0)
-                              > 0.0)
+                              > 0.0,
+                              cut=getattr(c, "room_charge", False))
     return out
 
 
@@ -1367,13 +1368,19 @@ def line_peak_not_covered() -> str:
     return _t("peak_not_covered")
 
 
-def line_period(period_w, limit_w, shadow, unmeasured=False) -> str:
+def line_period(period_w, limit_w, shadow, unmeasured=False,
+                cut=False) -> str:
     step = _w(shadow, "step_in", kw=_kw(limit_w))
     if unmeasured:
         # SAFETY-90: the add-on started during this period.
         return _t("period_unmeasured") + " " + step
     if period_w is None:
         return step
+    if period_w > limit_w:
+        # SAFETY-125: the figure is the current rate, and a grid charge is
+        # what gets cut back.
+        return _t("period_over", kw=_kw(period_w)) + " " + (
+            _w(shadow, "charge_cut", kw=_kw(limit_w)) if cut else step)
     return _t("period", kw=_kw(period_w)) + " " + step