Integrate or reference AnimateDiff in Google Colab notebook

A Google Colab notebook related to AnimateDiff exists here: https://colab.research.google.com/github/dmarx/notebooks/blob/main/AnimateDiff.ipynb

It would be useful to either officially maintain, document, or reference this notebook in the repository. This can help users easily get started using AnimateDiff with Colab support, and improve onboarding or reproducibility.

• Consider linking this notebook from the documentation or README
• Evaluate maintaining an official Colab notebook within the repo
• Optionally, review the notebook to keep it up to date with the latest AnimateDiff features

Reference: https://colab.research.google.com/github/dmarx/notebooks/blob/main/AnimateDiff.ipynb