Support for image previewer

**Is your feature request related to a problem? Please describe.**
I'm always frustrated when I have to open GUI git client to see changed images.

**Describe the solution you'd like**
It would be really nice to have image preview (before, after) within lazygit. Many terminals have great support for images (like kitty).

**Describe alternatives you've considered**
To see image diff I must open git GUI client.

**Additional context**
I use for example yazi and it works really well with images, similar solution should be introduced in lazygit.