Allow org.hibernate.type.Type to customize itself with the SQL type

[beikov]

Right now, org.hibernate.type.Type does not know what the SQL type is that it refers to, which is usually fine. To support JDBC array and struct types it is necessary to somehow allow the type create a variant of itself based on the SQL type. This is due to the fact that Connection.createArrayOf and Connection.createStruct need the SQL type name.

My suggestion is to add a method to the contracts BasicType and maybe also a similar one to CompositeType:

default BasicType<T> customize(String sqlTypeName) { // Maybe also pass Dialect if needed
    return this;
}

An array type or struct type could then use this sql type name to do what it needs to with the connection for reading/writing arrays/structs.

The sql type name would come from the columnDefinition as defined by the user, or if that is omitted, it would use the default type name as provided by the Dialect for the type code and size.

[beikov]

We decided to move the information into a dedicated type SqlTypedMapping that SelectableMapping extends.