Create llms.txt

[sanjeed5]

Overview: What does this pull request change?

Add's a llms.txt file for Manim. Reference: https://llmstxt.org/

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

I was trying to use an agent to work with Manim and thought of this

Further Information and Comments

I don't know if this is the right position for the file to be in, please comment and I"ll make necessary changes to complete this.

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

[JasonGrace2282]

I feel like this would be something better and easier to keep up to date for Sphinx (see sphinx-doc/sphinx#13268), but they seem to not have any interest in it currently.

[chopan050]

Thanks for the contribution! I left some comments and change requests.

[chopan050]

The links in this file are broken. To fix this, please add /en/stable right after docs.manim.community in all of them:

Suggested change

	- [Example Gallery](https://docs.manim.community/examples.html): A collection of code snippets and corresponding video/image outputs showcasing different Manim functionalities.
	- [Example Gallery](https://docs.manim.community/en/stable/examples.html): A collection of code snippets and corresponding video/image outputs showcasing different Manim functionalities.

[chopan050]

Although we briefly mention in this link that "The standard way of installing Manim is by using Python’s package manager pip", the method we actually recommend is using uv and the linked page almost exclusively talks about using uv when installing Python and Manim. Therefore, I believe that the description here should reflect that.

Suggested change

	- [Local Installation via pip](https://docs.manim.community/installation/uv.html): Recommended method for installing Manim using Python's package manager pip and uv for environment management.
	- [Local Installation via uv](https://docs.manim.community/en/stable/installation/uv.html): Recommended method for installing Manim using uv for environment management.

[chopan050]

Is this first line necessary? Other llms.txt files I've seen don't have it.

Suggested change

```markdown