MAINT-10: maintenance start hour in local time, default 19:00

The start hour was compared with the UTC hour, so the shipped 10 started at
12:00 in a Belgian summer. It is now read in Home Assistant's time zone
(fallback: the container's TZ, then UTC, one log line says which), and the
default moves to 19. DST: a missing hour starts at the first hour after the
jump; a repeated hour starts only in its first pass. Stored options are not
rewritten: a saved 10 now means 10:00 local (DOCS, CHANGELOG).

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

goodwe_controller/test_price_forecast.py

@@ -716,10 +716,11 @@ check("the drain's commitment window is DERIVED from the phase machine's own "
       "timeout, so the gate and maintenance.py cannot drift apart",
       near(MAINTENANCE_DRAIN.commits_h, DRAIN_TIMEOUT_MIN / 60.0)
       and near(MAINTENANCE_CHARGE.commits_h, CHARGE_TIMEOUT_MIN / 60.0))
-# The shipped `maintenance_start_hour` is 10:00 local, so a drain started on
-# schedule runs into the evening - hours a morning-only day-ahead print has not
-# covered. That is the ticket's scenario and it is where the window is placed.
-START = D0 + timedelta(hours=MaintConfig().start_hour)
+# A drain started at 10:00 local runs into the evening - hours a morning-only
+# day-ahead print has not covered. That is the ticket's scenario, so the hour is
+# pinned here: 10 was the shipped default until MAINT-10 moved it to 19, and an
+# install that stored 10 still starts then.
+START = D0 + timedelta(hours=10)
 _hours = derived(lambda: committed_hours(START, MAINTENANCE_DRAIN))
 check(f"...and it commits {len(_hours) if not isinstance(_hours, _Raised) else _hours} "
       f"whole hours, one per hour of the timeout",