Publish bootstrap-commits.yml as an artifact for each build

[avdgrinten]

This would allow us to reproduce exactly the source commits that are used in a particular build.

[ArsenArsen]

hm, there isn't really a place to put that in the current abstraction. I think it might be sensible to print it out to the coordinator log, if you agree? though, less convenient than a separate file of course

(there isn't such a place because the coordinator can only produce logs, really. introducing this would require some sort of coordinator artifacts so that it's not buildsystem-specific)

[avdgrinten]

The problem with printing out on stdout is that it's quite big.

Could we add some kind of dummy job that just emit the file?

[ArsenArsen]

actually, it could become a file in the artifact repository, there would just not be a corresponding artifact in the dependency graph (and no corresponding job) for it

that can be added relatively easily assuming we're okay with there being no link to it for now (I'm still not sure how I'd like to integrate that and other buildsystem-specific pieces of the xbbs-web UI into xbbs-web without making it a mess of special-cases)

[ArsenArsen]

~$ curl http://localhost:8000/projects/managarm/2025-10-20T09:35:54/repo/extras/bootstrap-commits.yml | jq
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100  1612  100  1612    0     0   445k      0 --:--:-- --:--:-- --:--:--  524k
{
  "commits": {
    "freestnd-cxx-hdrs": {
      "rolling_id": "126",
      "fixed_commit": "a6b351e0ab3e74e5789b01fa1447e4cd62373da7"
    },

[avdgrinten]

Sounds good. We can think about web UI integration as a second step.