otel span exceptions missing error messages

[jcaplan]

Initial Checks

• I confirm that I'm using the latest version of Pydantic AI
• I confirm that I searched for my issue in https://github.com/pydantic/pydantic-ai/issues before opening this issue

Description

as mentioned in #2925

when I insert an extra span in my toolsetwrapper I can see the error message:

but the running tool span does not show the error message properly:

It seems like the error message should be attached to the "event":

vs.

I think maybe the ToolRetryError should be passing through the error message to super().__init__() here

Example Code

Python, Pydantic AI & LLM client version

- python 3.12.7
- pydantic-ai=1.0.2
- AzureOpenAI client.