Grant the next month of credits to every Recognized/Elite creator whose billing month has closed.

Meant for a daily GCP Cloud Scheduler hit — it picks up whoever is due rather than assuming a fixed day, so each creator renews on the anniversary of the day they joined. Running it more than once a day is harmless: a subscription is only due while its current_period_end is in the past, and renewing pushes that a month forward.

A gap in the schedule does not compound. If the job is down for three months, the creator gets one month's credits and their renewal date is moved to the next future anniversary — credits are an allowance, not a balance that accrues.

limit is for a cautious first run in a new environment; leave it off in the schedule.