Better webp, gif rendering

[EricBAndrews]

Requirements

• There are no existing issues for this feature.
• This is a request for a single feature (create multiple issues for multiple feature requests).

Description

Webp and gif rendering is currently handled by SDWebImageSwiftUI's AnimatedImage, which works OK out of the box but needs some janky hacks to play nice with scrubbing and suffers from performance issues when scrubbing backwards. This view should be rewritten as a custom UIViewRepresentable around the core SDAnimatedImageView to offer better performance and more elegant scrubbing.

This should also enable displaying runtime and current play time on the playback bar.