fix(huggingface) : function_call_output conversion to support client-side tool execution

[shubham-021]

Background

The @ai-sdk/huggingface provider uses the OpenAI Responses API format, which requires tool results to be sent using function_call_output items. However, the current implementation only handles server-side tools and throws an "unsupported tool messages" warning when encountering client-side tool results (messages with role: 'tool'), causing the tool result to be skipped entirely

Summary

Added function_call_output conversion for client-side tool execution

Changes Made:

• Added HuggingFaceResponsesFunctionCallOutput type to match Responses API spec
• Replaced the "unsupported tool messages" warning with proper conversion logic
  - Converts role: 'tool' messages to function_call_output format
• Updated existing test to verify no warnings are produced
• Added test to verify function_call_output appears in request body

Manual Verification

• Added huggingface-tool-bug.ts file in example/ai-core/src/generate-text which produces the issue without the fix , with fix it produces the expected result.

Checklist

• Tests have been added / updated (for bug fixes / features)
• Documentation has been added / updated (for bug fixes / features)
• A patch changeset for relevant packages has been added (for bug fixes / features - run pnpm changeset in the project root)
• I have reviewed this pull request (self-review)

Fixes : #10766

[shubham-021]

@aayush-kapoor please review this PR when you get a chance. Thank you.