Ergonomics Catch-All Issue

[nrfulton]

This is a catch-all issue for tracking small and non-urgent quality-of-life issues we would like to fix prior to 1.0.0.

• from mellea.backends.types import ModelOption -> from mellea.backends import ModelOption.
• If tools is in the model_options passed to a backend, and also tool_calls=False, then an exception should be thrown informing the user that they should set tool_calls=True.
• Isolate and time-out tool calling: see Ergonomics Catch-All Issue #234 (comment)
• Subclass ValidationResult with ExecutionResult and ToolCallResult. Use these reseult types in tool-specific sampling strategies. FYI: @0xCUB3; see also feat: code_interpreter #232 (comment)

[nrfulton]

We should probably isolate tool calling -- at least calling a separate process and possibly sandboxing.

This is the minimum we should be doing:

@dataclass
class ModelToolCall:
    """A dataclass for capturing the tool calls a model wants to make.

    Provides a unified way to call tools post generation.
    """

    name: str
    func: Callable
    args: Mapping[str, Any]

    def call_func(self, timeout: float | None=None) -> Any:
        """A helper function for calling the function/tool represented by this object.
        
            Args:
                timeout: if set, the tool call will time-out and an exception will be thrown after `timeout` seconds."""
        if timeout:
            with multiprocessing.pool.ThreadPool() as pool:
                result = pool.apply_async(self.func, kwds=self.args).get(timeout=timeout)
                return result
        else:
            return self.func(**self.args)