Add type annotations to `three_dimensions.py`

[henrikmidtiby]

Overview: What does this pull request change?

Motivation and Explanation: Why and how do your changes improve the library?

Links to added or changed documentation pages

Further Information and Comments

Reviewer Checklist

• [ ] The PR title is descriptive enough for the changelog, and the PR is labeled correctly
• [ ] If applicable: newly added non-private functions and classes have a docstring including a short summary and a PARAMETERS section
• [ ] If applicable: newly added functions and classes are tested

[henrikmidtiby]

Maybe it's better to simply use Literal[False] in this PR, discuss the topic, and then possibly change it to None in a follow-up PR?

I would prefer that approach. The changes are quite easy to make (see https://github.com/ManimCommunity/manim/pull/4497/commits/d5c54cf5fa9c71d43d490700218109c554f45bfb), but it would be nice to discuss this among the developers.