These are all the animated emojis from https://googlefonts.github.io/noto-emoji-animation/ which are licensed under CC BY 4.0, directly useable for your project.
cargo add animated-emojis-rs
Alternatively you can choose to use a sparse checkout to fetch all the Lottie files in this repository.
Update the version in flake.nix, run a proxy server at http://127.0.0.1:3128 and run cargo test