Phase 6 Plan 3 complete. Async batch email notifications to opted-in
mentors on job publish without blocking admin workflow. Integrated with
Action Scheduler for background processing in batches of 50 users.
German email templates with job details, rate limit delays, error
logging, and unsubscribe hints.
Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
