Creating onFunctionCalls Callback

[toshiossada]

When request was finished it's not possible to trigger a callback, with this fix it's possible to give a callback onFunctionCalls geting the list of FunctionCall

Example how to use

  late final _provider = GeminiProvider(
    model: gemini,
    chatGenerationConfig: GenerationConfig(),
    chatSafetySettings: [],
    onFunctionCalls: (functionCalls) {
      for (var function in functionCalls) {
        final result =
            GeminiTools().handleFunctionCall(function.name, function.args);

        if (!result.success) {
          ScaffoldMessenger.of(context).showSnackBar(
            SnackBar(
              content: Text('Erro: ${result.reason}'),
              backgroundColor: Colors.red,
            ),
          );
        } else {
          model = result;
        }
        setState(() {});
      }
    },
  );

#98

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[csells]

@toshiossada that's pretty great. a couple of changes I'd like to see made:

1. this should be added to the vertex provider as well
2. I'm not quite on board with onDone -- I'm thinking something like onFunctionCall or onToolCall.

[toshiossada]

2. I'm not quite on board with onDone

I used 'onDone' because this is a callback will be triggered when request finish, don't necessarily for functionCall ou ToolCall

[csells]

I know. It should be. Otherwise why are you passing back only the last chunk response object?

[toshiossada]

Whats do you sugest?

[csells]

I'm thinking something like onFunctionCalls or onToolCalls

[toshiossada]

I'm thinking something like onFunctionCalls or onToolCalls

ok, DONE!

[toshiossada]

@csells anything else?