ci: block release on develop placeholder; create release via gh CLI

[zackkatz]

Follow-up to #26 (review feedback + safety catch):

• Release guard: refuses to launch a new version while readme.txt still contains a = develop = changelog placeholder — fails the job with a clear error instead of shipping an unfinalized changelog. Scoped to the release path so unrelated main merges are unaffected.
• gh release create instead of softprops/action-gh-release for the new-version release step; --target pins the tag to the exact commit the ZIP was built from. The rolling-latest and manual-tag backstop steps keep the action for its update-in-place semantics.

Validated: YAML parses; guard tested both ways (current readme passes, a = develop = fixture trips it).

Summary by CodeRabbit

• Chores
  • Enhanced release validation to prevent incomplete version markers from being deployed.
  • Improved release creation automation for better consistency and traceability.

💾 Build file (7e0f943).

[coderabbitai]

Walkthrough

The plugin release workflow now validates that readme.txt does not contain the = develop = placeholder before creating a release, preventing unreleased versions from being tagged. The release creation mechanism is migrated from the softprops/action-gh-release action to explicit GitHub CLI (gh release create) commands, passing the version and commit SHA through environment variables.

Changes

Release Workflow Automation

Layer / File(s)	Summary
Version validation guard .github/workflows/build-plugin-zip.yml	Version detection now checks if readme.txt contains = develop = placeholder and exits with error if found, preventing release creation for unreleased versions.
GitHub CLI release creation .github/workflows/build-plugin-zip.yml	Release creation switches from softprops/action-gh-release to gh release create, passing --target $GITHUB_SHA, --title, and --notes-file pointing to a temporary release notes file via environment variable configuration.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Possibly related PRs

• GravityKit/block-mcp#26: Both PRs modify the same GitHub Actions workflow to improve plugin version tagging and release creation automation based on readme.txt version detection.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and concisely summarizes the two main changes: blocking releases when a develop placeholder exists and switching to gh CLI for release creation.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.

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✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch develop

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