Function calls with 'id' fails with 400 using Gemini

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#### Environment details

- Programming language: Java
- OS: Linux
- Language runtime version: 17
- Package version: 1.8.0

#### Steps to reproduce

1. Use a multi agent setup using Java Google ADK (v 0.3.0) with a function call.
2. When LLM returns response to invoke a function call, agent invokes and sending the response back to Gemini causes `com.google.genai.errors.ClientException: 400 . Invalid JSON payload received. Unknown name "id" at 'contents[5].parts[0].function_call': Cannot find field.
Invalid JSON payload received. Unknown name "id" at 'contents[6].parts[0].function_response': Cannot find field.`
3. I patched the java-genai package to add @JsonIgnore in FunctionCall and FunctionResponse.
``
@JsonProperty("id")
@JsonIgnore
public abstract Optional id();
``
4. Ran the agent again, and it succeeded.

It looks like Google Gemini does not expect 'id' in Functions but java-genai sends it.

Making sure to follow these steps will guarantee the quickest resolution possible.

Thanks!