Either move the select from repeat section or add more links to it

https://docs.getodk.org/form-logic/#generating-select-ones-from-repeats

Hard to find from either repeats or `select_one`.

Start with the linked form-logic documentation section on generating select ones from repeats, then inspect how readers reach it from the repeats and select_one topics. Done means the section is discoverable from both relevant paths, either by moving it or adding appropriate links.

Written by the indexing model from the issue text.