add two @Apinotes about the role of Type

also, Type is definitely not @internal

Author: gavinking

hibernate-core/src/main/java/org/hibernate/Interceptor.java

@@ -47,6 +47,10 @@
  *          However, JPA callbacks do not provide the ability to access the previous
  *          value of an updated property in a {@code @PreUpdate} callback, and do not
  *          provide a well-defined way to intercept changes to collections.
+ *          <p>
+ *          Note that this API exposes the interface {@link Type}, which in modern
+ *          versions of Hibernate is considered an SPI. This is unfortunate, and might
+ *          change in the future, but is bearable for now.
  *
  * @see SessionBuilder#interceptor(Interceptor)
  * @see SharedSessionBuilder#interceptor()

hibernate-core/src/main/java/org/hibernate/type/Type.java

@@ -10,7 +10,6 @@
 import java.util.Map;
 
 import org.hibernate.HibernateException;
-import org.hibernate.Internal;
 import org.hibernate.MappingException;
 import org.hibernate.engine.spi.SessionFactoryImplementor;
 import org.hibernate.engine.spi.SharedSessionContractImplementor;
@@ -32,10 +31,17 @@
  * An implementation of this interface must certainly be thread-safe. Ideally, it should also be
  * immutable.
  *
+ * @apiNote
+ * This interface—which has existed since the very earliest days of Hibernate—used
+ * to be an important API. In modern versions of Hibernate its role has evolved, and it is no
+ * longer considered an API, though it's still a very important SPI. Application programs should
+ * avoid direct use of this interface where possible. In many cases,
+ * {@link org.hibernate.type.descriptor.java.JavaType} or
+ * {@link org.hibernate.type.descriptor.jdbc.JdbcType} may be used instead.
+ *
  * @author Gavin King
  * @author Steve Ebersole
  */
-@Internal
 public interface Type extends Serializable {
 	/**
 	 * Return true if the implementation is castable to {@link AssociationType}. This does not