Gif favourites only accepts true .gif files

[dollth-ing]

Describe the bug

Allot of "gif" files when presented in other spaces are actually an animated webp or apng, including those from klipy, support for these to be favourited in the gif picker would be nice

Reproduction

1. Upload animated webp
2. No favourite button appears

Expected behavior

Favourite button appears

Platform and versions

1. OS: Chimera Linux
2. Browser: Firefox 152.0
3. Sable Version: v1.18.3-dev (4d6137b)
4. Matrix Homeserver: Dollth.ing

Additional context

No response