feat: enable parallel tool execution in ToolInvoker

[Amnah199]

Related Issues

• fixes Investigate running Tools in Parallel in the ToolInvoker #9008

Proposed Changes:

• Update run_async to gather all tool_calls and execute them in parallel.

How did you test it?

Notes for the reviewer

Checklist

• I have read the contributors guidelines and the code of conduct
• I have updated the related issue with new insights and changes
• I 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 documented my code
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[coveralls]

Pull Request Test Coverage Report for Build 15872972654

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 84 unchanged lines in 10 files lost coverage.
• Overall coverage increased (+0.09%) to 90.278%

---

Files with Coverage Reduction	New Missed Lines	%
components/rankers/sentence_transformers_similarity.py	1	98.75%
components/generators/hugging_face_api.py	2	96.43%
components/routers/init.py	2	46.15%
dataclasses/init.py	2	23.08%
dataclasses/streaming_chunk.py	5	91.53%
components/generators/chat/openai.py	6	96.39%
components/generators/utils.py	9	75.0%
components/generators/chat/hugging_face_api.py	10	94.79%
utils/base_serialization.py	18	89.09%
components/tools/tool_invoker.py	29	87.76%

Totals
Change from base Build 15728854337:	0.09%
Covered Lines:	11709
Relevant Lines:	12970

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💛 - Coveralls

[mpangrazzi]

Looks generally good, I've added a few comments!

[sjrl]

@Amnah199 as a general comment could we align the implementations of run and run_async to match as closely as possible? I realize they can't exactly be the same, but it would be great if we could minimize the differences so they are easier to both update at the same time in the future. For example, self._prepare_tool_call_params is called before the ThreadPoolExecutor context in run but it is called inside of the context in run_async.

[sjrl]

Thanks looks good!