Automate Release Notes Creation

[anupriya13]

Worked automating the process of creating release notes so that we don't have to manually copy paste the commits.

Latest run 0.79: https://github.com/microsoft/react-native-windows/actions/runs/15104180584

Steps:
Fetches commit from start and end date range, ignores bots and publish the release notes to artifacts.

Artifact Latest 0.79:
https://github.com/microsoft/react-native-windows/actions/runs/15104180584/artifacts/3148688188

Updated this job to trigger on every release tag/ *-stable branches PRs with manual insertion of start and end date or update the default values from script.

Microsoft Reviewers: Open in CodeFlow

[TatianaKapos]

I think this a great starting off point and will definitely save some time!

Keep in mind that you will still need to manually go through each commit here and add an Summary/Explanation section and remove PRs that aren't useful to customers (ie anything to do with testing with our repo, experimental features that are still in progress, ect).

Also would this make more sense to just have as an internal script instead of running every time in the pipeline?

[TatianaKapos]

Feel free to look at previous release notes to get a feel! Notice the explanation/summary section will sometimes differ from the PR name.
https://github.com/microsoft/react-native-windows/releases/tag/react-native-windows_v0.78.0
https://github.com/microsoft/react-native-windows/releases/tag/react-native-windows_v0.77.0
https://github.com/microsoft/react-native-windows/releases/tag/react-native-windows_v0.76.0

You'll also still have to manually add any PRs backported into the stable branch before the release goes out

[TatianaKapos]

Is there a reason for this to be in the pipeline?

I feel like this would be most useful as an internal script such as "integrate-rn", especially if you're going to have to manually edit the workflow to get it to run and will only need to be run once in a stable branch

[anupriya13]

@TatianaKapos Makes sense, will turn it to a draft PR for reference only. Also, it's not in the Azure pipelines, it's in the GitHub Actions.