feat: endpoint to get HaRP version

[oleksandr-nc]

We will need this in AppAPI in the near future, some kind of endpoint so that we can tell the admins from AppAPI that their HaRP is old and not compatible with the new version of AppAPI. (as currently with DSP it is a disaster)

[kyteinsky]

Can we do automated checks for this, like an additional header in app_api for minimum supported version of harp? That is validated in the harp container and returns an error visisble in the logs.

[oleksandr-nc]

Can we do automated checks for this, like an additional header in app_api for minimum supported version of harp? That is validated in the harp container and returns an error visisble in the logs.

I thought of doing it this way initially, but it would greatly complicate the logic of work in AppAPI - where we would have to check the answers everywhere and it would be ugly.
And with this we will be able to simply check all HaRPs during the AppAPI update, for example, or at least during the "TestConnect" button - whatever we will choose.

I wanted to make it not too complicated

[kyteinsky]

fair enough :)