self-host proof parameters

[LesnyRumcajs]

Summary of changes

Changes introduced in this pull request:

• by default, use self-hosted proof parameters. In case of errors (or if forced by an environmental variable), fall back to the IPFS gateway. This should resolve numerous issues with the slow download and knocking out our GH jobs.

Even in good conditions, it's faster:

❯ export FOREST_PROOFS_ONLY_IPFS_GATEWAY=1
❯ time forest-tool fetch-params --keys
________________________________________________________
Executed in   11.83 secs      fish           external
   usr time  620.09 millis    0.00 micros  620.09 millis
   sys time  338.11 millis  276.00 micros  337.83 millis

❯ export FOREST_PROOFS_ONLY_IPFS_GATEWAY=0
❯ time forest-tool fetch-params --keys
________________________________________________________
Executed in    4.59 secs      fish           external
   usr time  399.09 millis  217.00 micros  398.87 millis
   sys time  244.08 millis   48.00 micros  244.03 millis

Reference issue to close (if applicable)

Closes

Other information and links

Change checklist

• I have performed a self-review of my own code,
• I have made corresponding changes to the documentation,
• I have added tests that prove my fix is effective or that my feature works (if possible),
• I have made sure the CHANGELOG is up-to-date. All user-facing changes should be reflected in this document.

[aatifsyed]

Your PR description should also live in the module documentation

[LesnyRumcajs]

Your PR description should also live in the module documentation

This module has no documentation - it's just a set of loosely coupled functions. I'll address it in a follow-up.