Manifest reform

[Gankra]

Works towards #843 by introducing top-level "systems" and "assets" maps, similar to artifacts, which are indexed by other items.

The biggest challenge of this is to rework the linkage subsystem to properly refer to binaries by id. It also adds inline checksum values to artifacts, with sha256 checksums being guaranteed on archives.

• add new fields to manifest (dummied)
• refactor build code for managing binaries
• compute linkage bottom up
• flow data to manifest
  • compute system ids ("{subcommand}:{artifacts_mode}:{targets.join(',')}"?)
  • compute asset ids (guid generated on the system that builds it?) (annoying for snapshot stability, might need safe mode...)
  • bubble linkage up so it can be stored in dist-manifest (or pass manifest down...?)
  • implement manifest merging for new fields
  • make artifacts[] reference assets[]
  • implement artifacts[] merging
  • add new artifact_uploads[] so it's okay for artifacts[] to contain old info
  • change ci.yml to use artifact_uploads[] instead of artifacts[]
• stop using old linkage format
  • make homebrew dep code read linkage from new manifest location
  • make linkage checker read linkage from new manifest location
    • honestly just remove cargo_dist's Linkage types, only use cargo_dist_schema's?
• make --artifacts=lies (build_fake) add fake linkage?

[Gankra]

https://github.com/Gankra/cargodisttest/releases/tag/v0.6.4

has a dist-manifest.json with the new system (see: assets[] and systems[])

[Gankra]

i've now added inline checksums to the manifest, and changed the homebrew code to use both that and New Linkage.

[Gankra]

lmfao, real fake checksums are uhhhh a problem for RUIN_ME_WITH_INSTALLERS, might need to make a tweak here...

(these RUIN_ME installer tests fetch the tarballs using live github data, on the assumption that we can reproduce the URLs exactly, but, this breaks if we generate installers which also insist they know the checksum...)

[Gankra]

nice, new checksum/brew stuff appears to have worked: https://github.com/Gankra/cargodisttest/releases/tag/v0.6.5

[mistydemeo]

In general I like the way this is going! I'm going to need to kick the tires a bit to get a feel for what the data looks like in practice, but I think the approach is valid! I'll do some testing on this soon and look at the resulting manifests.