[NEW] Get user's avatar as PNG, JPG or BMP with custom resize

[lindoelio]

@RocketChat/core

Closes #8178

Provides endpoint implements based on parameters for transform and resize avatars. For example: '/avatar/username?format=png&height=20&width=20' will ever return one PNG image with 20 pixels of width and 20 pixels of height. This will work either with PNG, JPG, BMP or SVG origin.

The supported formats for transformed output are: PNG, JPG and BMP.

[Lemmmy]

Seeing as this is a public endpoint, how is this cached and ratelimited? As image resizing can be a heavy operation (especially at large scales), I see potential for a DoS attack here.

[engelgabriel]

@Lemmmy the best place to cache this would be at the load balancer or at CDN, but we can think about storing the resized version on the file storage.

[sampaiodiego]

Closing since the PR is not compatible with the lib we're currently using for image manipulation.