fix #6881 - add policies for too long ids from a str and use short as default

[RonnyPfannschmidt]

this experiments with addign a policy and a new default

• short(default) - if the str is longer than 100, use the normal shorten
• hash: make a sha256 of the value
• legacy: just take the long str, for transitons
• disallow: juexpect people to pick ids

closes #6881