Contact name length limit

[vohmar]

There is no limit for registrant and contact name length on registry application level. There is a 256 character limit (varchar(256)) set in test database, but the same limit is missing in staging and production.

EPP base schema (https://datatracker.ietf.org/doc/html/rfc5730) sets the parameters for the name objects length to 1-255

Set the limits for the registrant and contact names to 255 characters. Fix the database schemas so that it's the same in staging, test and production environments (setting the limit on database level if possible)