[Junie]: Review PR diff and update README documentation

[junie-github-actions]

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• 🔗 Issue: Fixes: CI Failures agent #53

📊 Junie Summary:

Documentation Review Complete

Summary

Reviewed the PR diff for marco_ci_failures and compared it against README.md and COOKBOOK.md documentation. The PR introduces a new fix-ci trigger phrase feature while maintaining all existing functionality.

Key PR Changes Analyzed

1. Internal refactoring: Changed from json_output to json_output_file (internal implementation detail, not user-facing)
2. New feature: Added fix-ci trigger phrase and FIX_CI_ACTION constant
3. Enhanced CI failure analysis: Added isWorkflowRunFailureEvent and createFixCIFailuresPrompt functions
4. Test updates: Added tests for the new fix-ci functionality

Documentation Status

✅ README.md - Accurate and Complete

• All action.yml inputs/outputs correctly documented (7 outputs: branch_name, should_skip, commit_sha, pr_url, junie_title, junie_summary, github_token)
• Code examples are correct and functional
• Configuration examples match implementation
• CI Failure Analysis feature already mentioned in features list
• workflow_run event already documented in supported events
• No updates needed

✅ COOKBOOK.md - Updated

• Added documentation for the new fix-ci trigger phrase
• Documented two usage methods:
  • Comment-based: @junie-agent fix-ci
  • Prompt-based: prompt: "fix-ci"
• Explained what the built-in fix-ci action does automatically
• Positioned as an alternative to the existing workflow_run approach with custom prompt

Changes Made

Updated COOKBOOK.md section 3 ("Fix Failing CI Tests") to document the new built-in fix-ci trigger phrase, providing users with a simpler alternative to the custom prompt approach for CI failure analysis.