Add automated release notes generation workflow

[Copilot]

📝 Pull Request Summary

Implements automatic release.md updates on every commit and PR using conventional commit categorization.

🔧 Changes Made

• Workflow: .github/workflows/update_release_notes.yml

  • Triggers on push to main and PR events
  • Parses commits using conventional prefixes: feat:, fix:, docs:, test:, style:, build:, ci:
  • Maintains "Unreleased" section at top of release.md, preserving versioned releases below
  • Auto-commits changes via github-actions bot with [skip ci] flag
  • For PRs: analyzes base..head range; for pushes: uses commits since last tag

• Documentation: .github/workflows/README_update_release_notes.md

  • Conventional commit examples and categorization rules
  • Manual release process (rename "Unreleased" → "v{version}")
  • Workflow architecture and troubleshooting

Template adherence: Matches existing v0.6.1 structure with emoji-tagged sections (🚀 Features, 🐛 Bugfixes, 📝 Changelog with commit distribution stats)

Example output structure:

# Unreleased
...
## 🚀 New Features
* 2025-11-20 feat: add GPU optimization (%aN)
...
## 📝 Full changelog
| **5 commits** | 📚 Docs | ✨ Features | Other |
| % of Commits  | 20.0%   | 40.0%       | 40.0% |
---
# v0.6.1
[existing versioned content preserved]

✅ Checklist

• Code follows the project's style and guidelines
• Added tests for new functionality
• Updated documentation (mentioned in docs/ or included in examples/ and notebooks/)
• Verified that changes do not break existing functionality (automatic tests passing)

📌 Related Issues / PRs

Addresses request to auto-generate release.md using previous release template format.

Original prompt

Hello, can you work on a release.md everytime I perform a commit or a pull request? You can use the template of previous releases

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