Fix: Use heredoc syntax for multi-line GITHUB_OUTPUT in release workflow

[jasonsiders]

The release workflow was failing when multiple packages were detected because the packages output was written using the simple key=value format, which doesn't support multi-line values. GitHub Actions was rejecting the pretty-printed JSON array with the error Invalid format ' {'.

The fix switches to the heredoc delimiter syntax (key<<EOF ... EOF) for writing to $GITHUB_OUTPUT, which correctly handles multi-line strings. This was surfaced by the Repo Cleanup PR (#165), which triggered detection of two packages simultaneously.

[github-actions]

✅ Static Analysis: Check Passed

Analyzed changed files, and found 0 potential violations. 0 meets or exceeds the set severity threshold: Info

⚫ 0 Critical severity violation(s)
🔴 0 High severity violation(s)
🟠 0 Medium severity violation(s)
🟡 0 Low severity violation(s)
⚪ 0 Info severity violation(s)

[github-actions]

Claude finished @jasonsiders's task —— View job

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Pull Request Review ✅

Tasks:

• Read repository guidelines (CLAUDE.md) - No repo-specific guidelines found
• Examine the workflow file changes
• Analyze code quality and best practices
• Check for potential bugs or issues
• Evaluate performance considerations
• Review security concerns
• Assess test coverage implications
• Provide comprehensive feedback

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Review Feedback

✅ Code Quality and Best Practices

The fix correctly addresses the GitHub Actions limitation with multi-line output values. The solution follows GitHub Actions best practices:

• Proper heredoc syntax: Using <<EOF delimiter is the correct approach for multi-line output
• Clean implementation: The block structure { ... } >> "$GITHUB_OUTPUT" is well-formatted and readable
• Maintains functionality: The change preserves the existing logic while fixing the output format issue

✅ Bug Fix Analysis

This is a solid fix for a real issue:

• Root cause identified: GitHub Actions rejects multi-line values in simple key=value format
• Appropriate solution: Heredoc syntax (key<<EOF) is the standard way to handle multi-line strings in GitHub Actions
• Error pattern match: The fix addresses the specific Invalid format ' {' error mentioned in the PR description

The change from:

echo "packages=$PACKAGES" >> "$GITHUB_OUTPUT"

To:

{
  echo 'packages<<EOF'
  echo "$PACKAGES"
  echo 'EOF'
} >> "$GITHUB_OUTPUT"

Is exactly what's needed for multi-line JSON output.

✅ Performance Considerations

• No performance impact: The change is purely syntactical for output formatting
• Same computational complexity: JSON processing and variable assignment remain unchanged
• Minimal overhead: The heredoc approach has negligible performance difference

✅ Security Concerns

• No security risks introduced: The change only affects output formatting
• Input sanitization unchanged: JSON parsing and variable handling remain the same
• No injection vulnerabilities: The heredoc delimiter (EOF) is static and safe

✅ Test Coverage

• Workflow logic unchanged: The core package detection and JSON building logic remains identical
• Output format preserved: The JSON array format sent to dependent jobs is unchanged
• Integration testing: The fix resolves the workflow failure, which serves as integration validation

📋 Additional Observations

1. Good timing: This fix was surfaced by the Repo Cleanup PR (Repo Cleanup #165) detecting multiple packages simultaneously - good catch!

2. Consistent with GitHub Actions docs: The heredoc approach aligns with GitHub's official documentation for multi-line outputs

3. No breaking changes: Downstream jobs consuming packages output will receive the same JSON format

✅ Overall Assessment

This is a well-targeted fix that solves a specific GitHub Actions limitation without introducing any side effects. The implementation follows best practices and maintains the existing functionality. The PR is ready for merge.

Recommendation: Approve ✅

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