Supervisor integration

[CvekCoding]

I faced the problem with updating the maps.
The process nominatim replication --project-dir /nominatim works some time and then crashes.
So I've added supervisor to wrap replication process to make it stable.

[leonardehrenfried]

I must admit I'm not enthusiastic about adding a supervising wrapper around the update process since nominatim itself has some logic to retry.

I'd much rather fix the underlying problem of the crashes. Could you say a bit more about this?

[MichaelKorn]

I have similar observations on a world instance with daily updates. Each one or two months I realize in the UI that the instance is outdated (no update since a few days). Then I trigger the replication via docker exec nominatim bash -c "cd /nominatim && sudo -E -u nominatim nominatim replication" and it is fine again for a few weeks/months.
So far I haven't been able to find a cause, unfortunately there seem to be no logs for the update mechanism.

Please note: This problem is independent of the current issue of failing updates with version 4.2.2 (osm-search/Nominatim#3022).