* (Doc+) Link API to parent Doc part1
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Co-authored-by: shainaraskas <shaina.raskas@elastic.co>
Co-authored-by: shainaraskas <58563081+shainaraskas@users.noreply.github.com>
Explains its purpose and surrounding context a little more, including a
note that this should never be necessary (i.e. if you find you need it,
that's a bug).
This introduces an endpoint to reset the desired balance.
It could be used if computed balance diverged from the actual one a lot
to start a new computation from the current state.
