CustomerMetadataManagementInterface
Magento\Customer\Api\CustomerMetadataManagementInterface
What it does
This interface defines the contract for managing customer entity metadata and attributes in Magento 2.
Developers use this interface when they need to programmatically work with customer attribute metadata, such as retrieving, validating, or manipulating customer attribute definitions.
It extends the base MetadataManagementInterface and specifically identifies 'customer' as the entity type through its constant.