Release Source: GitHub Tags

[dwhswenson]

This also includes a translation that maps names of known packages to repos (e.g., "python" becomes "python/cpython").

TODO:

• Add this into the main CLI; if the package looks like a repo name or is in the list of known repos, we default to using GitHub
• Testing should probably include (optionally?) smoke tests on all known names

[codecov]

Codecov Report

Attention: Patch coverage is 99.63899% with 1 line in your changes missing coverage. Please review.

Project coverage is 99.29%. Comparing base (c267b53) to head (fa1a7bd).
Report is 19 commits behind head on main.

Files with missing lines	Patch %	Lines
src/spec0/releasesource.py	98.79%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main       #9      +/-   ##
==========================================
+ Coverage   99.18%   99.29%   +0.10%     
==========================================
  Files          15       15              
  Lines         616      853     +237     
==========================================
+ Hits          611      847     +236     
- Misses          5        6       +1     

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[Copilot]

Copilot reviewed 8 out of 10 changed files in this pull request and generated 1 comment.

Files not reviewed (2)

• MANIFEST.in: Language not supported
• src/spec0/data/github-releases.json: Language not supported

Comments suppressed due to low confidence (1)

src/spec0/releasesource.py:115

• [nitpick] Consider using package.count('/') == 1 for checking the 'owner/repo' format, which is more efficient and clear.

if collections.Counter(package).get("/") == 1:

[ethanholz]

LGTM, merging