Find orgs willing to host Heads/coreboot tarball mirrors from Purism

Nobody has claimed this yet.

pur.ism domain went offline yesterday, as reported in many places over Matrix channels from at home ROM builders.

As of today, only one mirror is available for packages https://github.com/linuxboot/heads/blob/51ade5bd10f6866f5a1afc5442ac5d2bc3aa7a20/bin/fetch_source_archive.sh#L6

This DNS renewal problem is not the first nor will be the last, but in puri.sm case, prevented matrix, CircleCI compilation of some packages, Purism forum, main website and all puri.sm subdomains to be reachable.

I contacted Todd by email from registrar public reference, but that email was read only late and no action was took in a timely matter so that working hours of registrar permitted fixing the issue in a timely manner. _Having one mirror is better then none, having many would be better_. Even more if tarballs would be unified, but where we still reply on puris.sm for coreboot forks and github for mostly anything needed otherwise, but as tarball hacks. This should be generalized so that tarballs is norm for everythig and cached and mirrored, and used.

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Two solutions for the future :
- Administrators/ Point of contact should be managed offline so that maintainers/stakeholders can be contacted from secondary channels (phone, emails. other communication channels)
- Other mirrors need to be added so that this cannot happen for future commit of that one adding new mirrors in the future https://github.com/linuxboot/heads/blob/51ade5bd10f6866f5a1afc5442ac5d2bc3aa7a20/bin/fetch_source_archive.sh#L6

@JonathonHall-Purism ?

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Some ongoing discussions for rsync mirroring would be interesting, but that would require Purism setting that up first @JonathonHall-Purism

Start with bin/fetch_source_archive.sh at the referenced line to understand the current package mirror configuration and how tarballs are fetched. Review the linked discussion and identify organizations willing to host mirrors; the work is complete when a durable, agreed mirror arrangement is documented and the fetch process no longer depends on a single source.

Written by the indexing model from the issue text.