Deterministic indices syncer

@markus.blatt: can you have a look?

Looks perfect. Thanks a lot.

approved this merge request

enabled an automatic merge when the pipeline for ccf70d50 succeeds

merged

mentioned in commit a658c135

mentioned in merge request !1152 (closed)

mentioned in merge request !1338 (merged)

See more details in !1152 (closed)

Thanks for the cross-link. We should have mentioned that of course and made a better description. My bad.