Add a housekeeping function to purge old history

[luebbe]

Describe the problem

As asked and answered in discussion #13324, there is right now no command/function to clear up old history.

In this example Weblate shows close to 40.000 pages of history, most of which are obsolete, since they date back several years.

Describe the solution you would like

I would like to be able to define a time span (xxx days/weeks/months/years) after which older history entries will automatically be purged. Add a meaningful default (e.g. one year).

I'm not sure whether this should be configurable from the admin page via the web UI or only inside the installation folder, unreachable via the web UI. Something similar is already available for the notifications which are sent on behalf of inactive projects. I can't find a UI page for it, so it is probably done on the installation configuration level.

Describe alternatives you have considered

No response

Screenshots

No response

Additional context

No response

[github-actions]

This issue has been put aside. It is currently unclear if it will ever be implemented as it seems to cover too narrow of a use case or doesn't seem to fit into Weblate.

Please try to clarify the use case or consider proposing something more generic to make it useful to more users.

[nijel]

What is actually the issue we are going to address here? Storage? Navigation issues? I still think that it is useful to see that string has been added five years ago.

[luebbe]

In that case it should be entirely optional, so maybe the default purge option should be off.

Since I don't know how much storage the history consumes i cannot say if it is a storage issue. If the entire history goes into each backup, it may become a storage issue for the IT in the long run.
For me personally it is information overload. It is just an "endless" list of changes. Maybe I would look at the latest 5-10 pages, but even then only human edits would be interesting to me. And if I'm interested in the changes made by a user, I'd go via his/her profile.

[nijel]

While it might be endless history when looking at the project level, it might be just a few change entries for each of the strings.

As for the storage size, I've looked at https://hosted.weblate.org/ and the changes table takes about the same size as the table storing strings. So I'd say this is acceptable use.