ci: rebuild release workflow

[WH-2099]

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Related Issue

Closes #36

Summary

• rebuild the release automation around a tag-triggered draft/TestPyPI/PyPI pipeline
• remove Cocogitto and CHANGELOG.md from the release path
• switch maintainer version updates to manual uv version --no-sync --bump ... commands
• reference commit: c99b220

Checklist

• This pull request links the issue it resolves or advances
• This pull request title follows Conventional Commits, and any breaking change is marked with !
• If CLA Assistant prompted me, I signed CLA.md in the pull request conversation