release: replace withdrawn v7.0.0 with v6.1.0

[zkoppert]

Why

I withdrew 7.0.0 to replace it with a minor-numbered 6.1.0 release. I retained the same functional contents, including the known breaking CommonMarker changes.

I retained the original tag for traceability. Existing downloads cannot be recalled; the number of affected downstream applications is unknown.

What changed

I updated GitHub::Markup::VERSION, the lockfile's local package version, and HISTORY.md. I kept every renderer implementation and third-party dependency requirement and pin unchanged from v7.0.0.

I added the 6.1.0 history entry and retained the 7.0.0 entry with a withdrawal notice. The CommonMarker compatibility and line-break changes remain documented and unchanged.

Source metadata	Before	After
Package identity on master	7.0.0	6.1.0
Renderer behavior and dependencies	Original v7.0.0 payload	Unchanged
Historical 7.0.0 entry	No withdrawal marker	Retained and marked withdrawn
Original v7.0.0 tag	Merged release commit	Unchanged

Alternatives considered

I chose version reclassification rather than restoring the older CommonMarker behavior. The minor version number does not mean the documented compatibility changes were reversed.

Testing

I ran the full 62-test suite in a fresh Codespace with RDoc 7.2 and 8.1. Both runs passed.

I built and clean-installed the 6.1.0 gem outside the source checkout. I verified the package version, Ruby requirement, runtime dependencies, and actual Markdown, RDoc, and reStructuredText rendering.

I haven't run application/browser acceptance. I explicitly waived that manual check for this unchanged functional payload, using the completed automated and package checks.

Rollout

I verified that RubyGems no longer lists 7.0.0 for installation. I marked its GitHub Release withdrawn without deleting or moving the tag.

I haven't published 6.1.0 or created its tag. Required maintainer approval and merge must finish before publication.

Existing ~> 6.0 constraints accept 6.1.0 but exclude 7.0.0. Dependency updates can therefore adopt the retained breaking behavior.

The gem does not declare a commonmarker runtime dependency; consumers using that renderer must check its version themselves.

After publication, I'll verify the new tag target, downloaded gem checksum, and latest-release status on RubyGems and GitHub.

Withdrawing 7.0.0 does not modify existing installations. Constraints such as ~> 7.0 won't select 6.1.0; users must update those constraints to install the replacement.

[Copilot]

🔵 Needs a closer look

Publishing retained breaking changes as a minor release risks incompatible updates for existing 6.x consumers and requires maintainer review.

1 open issue

• Breaking changes incorrectly published as 6.1.0 · New

What changed in this PR

Reclassifies github-markup’s withdrawn 7.0.0 release as 6.1.0, preserving renderer behavior and dependency requirements.

Changes:

• Align source and lockfile package versions at 6.1.0.
• Add replacement release notes and retain the withdrawn release’s history.

File	Description
lib/​github-markup.rb	Changes the version constant to 6.1.0.
HISTORY.md	Documents the replacement, compatibility changes, and withdrawal.
Gemfile.lock	Updates the local package version to 6.1.0.

_{Review effort: Max}