HHH-1904 cause non-explicitly named constraints to use randomly generated hex characters. Instead, it would be better to go back to a scheme that uses the table and column names, allowing naming consistency and control over the name length.

Concat the table and column names, md5 it, then convert the hex to base 35 (full alphanumeric). This guarantees a < 30 character hash.

In addition, take this a step further. Wrap the implicit, generated naming into a new contract: ConstraintImplicitNamingStrategy. The default strategy does the above, but we would allow applications to define their own strategies to fit in with their existing naming conventions.