fix: Add missing init param to to_dict in hf doc embedder

[sjrl]

Related Issues

• fixes #issue-number

Proposed Changes:

Fixed HuggingFaceAPIDocumentEmbedder serialization to preserve the configured concurrency_limit.

How did you test it?

Updated tests

Notes for the reviewer

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• I have updated the related issue with new insights and changes.
• I have added unit tests and updated the docstrings.
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Project	Deployment	Actions	Updated (UTC)
haystack-docs	Ready	Preview, Comment	May 18, 2026 8:40am

[claude]

Code review

No issues found. Checked for bugs and CLAUDE.md compliance.

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Coverage report

Click to see where and how coverage changed

File	Statements	Missing	Coverage	Coverage (new stmts)	Lines missing
haystack/components/embedders
hugging_face_api_document_embedder.py
Project Total

This report was generated by python-coverage-comment-action

[sjrl]

Errors are unrelated to changes I made. Looks like an issue on HuggingFace's end.

[sjrl]

@julian-risch could you review this when you have the chance?