Email - Broadcasts

Ad-hoc mass emails to a filtered set of clients with per-client Liquid token rendering. Provides draft CRUD, a pre-send resolved recipient list with skip warnings (missing contacts, email contact preference), per-client preview, test send to the current user, async sending with progress counters, a per-client delivery log, and cancellation. Recipient selection combines client filters with hand-picked additions and exclusions; recipients are resolved from client contact types, user types (manager/partner/associate/service manager), and static addresses — the same configuration shape as SendEmail workflow steps.