Extract merge commit body for release notes instead of PR description

[Copilot]

Release notes were using PR description instead of merge commit message body. Changed to extract merge commit extended description and combine with PR commit history.

Changes

• resolve_pr step: Fetch merge commit via merge_commit_sha and extract message body via GitHub API

  • Previous: Used $merged.body (PR description)
  • Now: Uses merge commit message body from API

• parse_commit step: Added GitHub API call to retrieve merge commit body for PR events

  • Previous: git log -1 --pretty=format:"%b" HEAD (unreliable)
  • Now: Uses github.event.pull_request.merge_commit_sha with API fallback to git log

• Release notes format: Merge commit body (personalized notes) appears first, followed by separator and categorized commit history

Usage

Write personalized release notes in merge commit message body:

Merge pull request #123 from feature/xyz

Custom release notes here.
Additional context for users.

The extended description (lines after first) appears at top of release, followed by automatic commit categorization.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>clannk</issue_title>
<issue_description>in release yml the very top release note grabs the ddescription of the pr but i actually want it to grab the extended descriptionb of the actual merge commit like it used to be in very old versions of release.yml

some time ago we changed it to be a list of the commit history in the PR and that worked but I wanted to write more personalized release notes as well so i want BOTH combined

copilot: do NOT touch the main.cpp file or i will fry you into a pile of bolts /j</issue_description>

<agent_instructions>for documentation, don't make any markdown files, just put comments in the pr or the file itself</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes clannk #66

---

💬 We'd love your input! Share your thoughts on Copilot coding agent in our 2 minute survey.