docs: add release note for AI Badgr provider documentation

[ghost]

Proposed Changes:

Previous PR added AI Badgr provider documentation but missed the required release note. Added releasenotes/notes/add-aibadgr-provider-documentation-987d5e6923e042.yaml documenting the feature.

AI Badgr is OpenAI-compatible, uses existing OpenAIChatGenerator with custom api_base_url. No code changes required.

How did you test it?

• Pre-commit hooks validation
• Code review tool
• Manual verification of release note format against existing examples

Notes for the reviewer

Release note follows project conventions. Single YAML file addition completing documentation from PR #1.

Checklist

• I have read the contributors guidelines and the code of conduct.
• I have updated the related issue with new insights and changes.
• I have added unit tests and updated the docstrings.
• I've used one of the conventional commit types for my PR title: fix:, feat:, build:, chore:, ci:, docs:, style:, refactor:, perf:, test: and added ! in case the PR includes breaking changes.
• I have documented my code.
• I have added a release note file, following the contributors guidelines.
• I have run pre-commit hooks and fixed any issue.

[vercel]

@miguelmanlyx is attempting to deploy a commit to the deepset Team on Vercel.

A member of the Team first needs to authorize it.

[CLAassistant]

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1 out of 2 committers have signed the CLA.

✅ miguelmanlyx
❌ Copilot
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[sjrl]

Hey @miguelmanlyx thanks for the contribution! We don't usually add dedicated docs pages in the main repo for integrations that are compatible with existing OpenAIChatGenerator.

What we do instead is highlight compatible providers in the https://github.com/deepset-ai/haystack-integrations repository, similar to the existing pages for llamafile and vLLM that also rely on OpenAIChatGenerator.

So it'd be great if you could move this documentation to https://github.com/deepset-ai/haystack-integrations

[vblagoje]

@sjrl let's close this PR

[sjrl]

Closing for now. @miguelmanlyx feel free to open a new PR in the repo mentioned in this comment