♻️ Refactor type annotations for `.remote()` to avoid incorrect autocompletion and checks (#25480)
♻️ Refactor type annotations for `.remote()` to avoid incorrect autocompletion and checks (#25480)

With the current type annotations for the `.remote()` method generated in decorated functions, editors understand that there are some keyword arguments `arg0`, `arg1`, etc. Which are incorrect as the actual function will probably have different names for its arguments.

For example, this shouldn't autocomplete `arg0`, `arg1`, etc:

<img width="407" alt="Screenshot 2022-06-04 at 06 13 46" src="https://user-images.githubusercontent.com/1326112/171996654-12248369-cf10-4fce-9ea2-5deb4ca8e2bd.png">

If anything, it should autocomplete `x` and `y` (although that's currently [not perfectly doable](https://github.com/python/typing/discussions/1163)).

By updating the type annotations to use [arguments prefixed with double underscores](https://mypy.readthedocs.io/en/stable/protocols.html?highlight=double%20underscore#callback-protocols) at least it tells tooling to not provide autocompletion for those args (which would be incorrect). While still providing inline errors for invalid types.

<img width="880" alt="Screenshot 2022-06-04 at 06 20 26" src="https://user-images.githubusercontent.com/1326112/171996806-560c0fa8-0ee3-477c-9906-71e880c84e56.png">
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