Completes the server side of #392 Half B.
PUT /api/me/timezone now calls scheduler.Refresh(ctx, userID) after
the DB write so the rescheduled daily-at-03:00-local job takes
effect synchronously. Failure to refresh is logged but doesn't
undo the DB write — the hourly reconciliation pass would pick it
up within an hour regardless.
POST /api/auth/register calls Refresh after successful user
insert so brand-new users get scheduled immediately rather than
waiting for the hourly pass to discover them.
system_cron.go deleted: the new scheduler subsumes its
responsibilities. The StartSystemPlaylistCron call in main.go is
also removed. Server restart now runs the new scheduler's startup
recovery + catch-up instead.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
bvandeusen
7fac264c73