📄️ Create a Pix account config (block) for accounts.
Owner-only endpoint that creates a PixAccountConfig of the informed name (always ACTIVE) for the selected accounts. Set apply_to_all=true to reach every wallet/pix account of every target user under the owner product, or send an explicit items array to target specific wallet+pix_account pairs. Existing configs are left untouched (use the update endpoint to change their state).