generalize setUitv1, setU1itv, setDitv1{l,r}, and add similar lemmas

[t6s]

Motivation for this change

This PR does

• generalize setUitv1, setU1itv, setDitv1{l,r},
• add similar lemmas such as setUitv2, setDitv2, setDitvoo, etc.

#1848 (comment)

I am not confident about the names of two added lemmas: setDcitvy and setDcitvNy,
and want reviewers to suggest better ones if any.

Checklist

• added corresponding entries in CHANGELOG_UNRELEASED.md

- [ ] added corresponding documentation in the headers

Reference: How to document

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