Add LIFECYCLE tests that wire an entry via make_entry(options=...) and
call async_setup_entry, covering the from_options_resilient fallback
production actually uses (P2): a fully malformed options dict
(horizon_days=True, day_rollover_time='99:99',
morning_summary_time='25:00') succeeds with the day-rollover listener
at the default 00:00 and the backfill over DEFAULT_HORIZON_DAYS; and a
bad sibling (horizon_days=5, morning_summary_time='25:00') keeps
horizon_days == 5. Swapping from_options_resilient for from_options in
setup now fails these tests.
Reword comments/tests describing review history rather than the code:
__init__.py setup comment, test_core_settings P2-3/P2-1/P2-5 markers,
the moved from_options horizon test, and the AST scanner docstrings.
Test hygiene: move freeze_nestquest_clock into tests/conftest.py and
use it from test_core_settings and test_timezones; simplify CORE_PKG to
a plain import plus Path(mod.__file__).parent; move
test_from_options_horizon_validates_and_defaults into test_core_settings.
1575 passed.