Engagement smart lists and multiple email fields per contact

Two audience upgrades. First, smart lists and campaign segments can now filter on real engagement: build a segment like "opened a campaign in the last 30 days", "hasn't opened anything in 90 days", "has not opened Campaign X", or "opened at least 3 campaigns this month" - using new engagement conditions (last emailed / opened / clicked dates, per-campaign opened/clicked/received, and 30/90-day counts) alongside the existing 0–100 engagement score. They work everywhere conditions do: dynamic lists, campaign refinements, and exclusions (like "skip anyone emailed in the last 7 days"). Second, records with multiple email fields are handled properly: each list now has an ordered email-field priority - say work email first, then general, then personal - and every campaign sends to the first field holding a valid address per recipient. Fallbacks only cover empty or invalid values; an unsubscribed address is never bypassed by rotating to another one. Because any object can be an audience in Solstral, both features work identically for contacts and for any custom object you email.