.Net Google Connector: Implement Audio input

[Cordelia242]

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name: .NET Google Connector: Implement Audio input about: Currently the interface chatCompletionService allows audio input but the google conector does not implement it

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Audio on the ChatHistory should be mapped and implemented on the google connector, example:

ChatHistory history = []; 
history.AddUserMessage([new AudioContent(audio, "audio/wav")]);

var response = await chatCompletionService.GetChatMessageContentAsync(
  history,
  new GeminiPromptExecutionSettings()
  {
...
  }
);

the audio should be sent to the google api