Emit OTel spans for tool calls that don't have an `execute` function

[armans-code]

Description

Right now, tool call spans are only created if they have a defined execute function. This means that tool calls that don't have an execute function aren't picked up in tracing. Thus, the only way to tell which tool calls were picked is to manually parse + look at the ai.response.toolCalls attribute of a doGenerate/doStream span.

It'd be great if these "noop" tool calls were captured in tracing, so we know when they're called.

This is helpful for tracing the following scenarios:

• forwarding tool calls to the client
• Custom tool execution control

Added a draft PR for proposed changes: #10499

AI SDK Version

ai: ^5.0.89

Code of Conduct

• I agree to follow this project's Code of Conduct