docs: add docstring and return type to DotFlow.result()

[alexkore12]

Summary

Fixes #83

Adds the missing docstring to DotFlow.result() for consistency with the other result_* methods.

Changes

• Added docstring to result() method describing its return value
• Added -> dict return type annotation

Before

def result(self):
    return self.task.result()

After

def result(self) -> dict:
    """
    Returns:
        dict: Returns the full workflow result serialized as a dictionary,
              including workflow ID and all task schemas.
    """
    return self.task.result()

[FernandoCelmer]

Thanks for the contribution, @alexkore12! 🎉

The docstring addition was already merged via PR #86. Your other PR #94 (execution typo fix) has been merged. Thanks for your contributions!