Apply an automatic top-up rule

Applies the exact unexpired automatic top-up preview a billing owner confirmed. Enable or expanded limits require this explicit approval; edit and disable fence queued unsubmitted work, while submitted or uncertain payments retain their original identity and UTC authorization month. Resume may clear only an authenticated payment-method failure and never an unresolved provider outcome. Applying a rule creates no charge; later low-balance work remains bounded by the approved fixed amount, one outstanding operation, cooldown, usage cap and gross monthly ceiling.