ci: align release changelog with template-repo format

[AndrewAltimit]

Summary

• Restructure the Generate changelog step to match template-repo's pattern: initialize CHANGELOG variable outside the PREVIOUS_TAG conditional, check emptiness separately, and add status messages
• Move GITHUB_TOKEN env to step-level (after run: block) matching template convention
• Remove unnecessary sed whitespace stripping from release notes heredoc
• Add id: release_notes to the release notes step for consistency

The gh api repos/.../releases/generate-notes call produces a ## What's Changed section with merged PR links and a Full Changelog comparison URL, which is appended after the --- separator in release notes.

Test plan

• Trigger a manual workflow dispatch with create_release: true to verify the release notes include the "What's Changed" section
• Verify the changelog snippet generates correctly by checking the has_changelog output

Generated with Claude Code

[github-actions]

Gemini AI Code Review

Issues (if any)

(none)

Previous Issues (for incremental reviews)

(none)

Suggestions (if any)

(none)

Notes

• 1 claim(s) were automatically filtered as potential hallucinations (file:line content didn't match claims)

• Restructured the Generate changelog step to initialize variables correctly and provide clearer status messages in the CI logs.

• Moved GITHUB_TOKEN to step-level environment variables, following the project's preferred convention for tighter scoping.

• Verified that the removal of the sed command for whitespace stripping is safe; the YAML block scalar (|) and the aligned indentation of the heredoc content ensure that release_notes.md [UNVERIFIED - File does not exist and is not in PR] is generated without unwanted leading spaces.

• The use of printf '%s\n' for writing the changelog snippet is a robust choice for handling arbitrary content returned by the GitHub API.

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Generated by Gemini AI (gemini-3-flash-preview). Supplementary to human reviews.

[github-actions]

Codex AI Code Review

Issues (if any)

(none)

Previous Issues (for incremental reviews)

(none)

Suggestions (if any)

(none)

Notes

• No actionable bugs, security issues, or required fixes were identified in the changed workflow lines in .github/workflows/main-ci.yml.
• The changelog generation and release-notes changes appear behaviorally consistent with prior logic in the reviewed diff.

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Generated by Codex AI (gpt-5.3-codex). Supplementary to human reviews.

[AndrewAltimit]

Review Response Agent (Iteration 1)

Status: No changes needed

Fixed Issues

• (none — no issues were reported)

Ignored Issues

• (none — no issues were reported)

Deferred to Human

• (none)

Notes

• Both Gemini and Codex reviews found zero issues, zero suggestions, and no bugs in PR ci: align release changelog with template-repo format #13 (ci: align release changelog with template-repo format).
• Gemini had 1 claim auto-filtered as a potential hallucination (referenced a file not in the PR), but that was handled by the review pipeline's claim validator — no action needed.
• No code changes required for this iteration.

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The agent reviewed feedback but determined no code changes were required.