Add function/tool call support in Workflow

[davinwang]

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1. Is this request related to a challenge you're experiencing? Tell me about your story.

I was trying to use function/tool call in Workflow, however I can only find it in Agent page. I need to access function/tool call in workflow in either way: add Agent to workflow,or add function/tool call in Workflow. Thx

2. Additional context or comments

No response

3. Can you help us with this feature?

• [X] I am interested in contributing to this feature.