Bug: _days_to_expiration uses datetime.now() — off-by-one on expiration day

[bradsmithmba]

Summary

datetime.strptime(expiration, '%Y-%m-%d') produces midnight of the expiration date. datetime.now() includes the current time of day. At 3pm on expiration day, (midnight - 3pm).days == -1, triggering the days <= 0 early return in _calculate_probability_above and incorrectly excluding valid options from the expiration filter.

Evidence

src/api/enhanced_strategy_recommender.py lines 587-589:

exp_date = datetime.strptime(expiration, '%Y-%m-%d')
return (exp_date - datetime.now()).days

Fix

return (exp_date.date() - datetime.now().date()).days

Comparing dates (not datetimes) gives the correct calendar-day count.