Updates to visual_shaders.rst to show new way to create visual shaders

[rametta]

The explanation for creating visual shaders seems to be outdated. There is no more option for creating a visual shader right below a normal shader, now you must pick visual shader by picking the correct "type" from the create shader dialog. This PR updates the docs and images to reflect this new workflow

[skyace65]

Two issues with those images. One they're way too big, I'm assuming you took screenshots on a 4K screen, those need to be scaled down. Additionally, we're changing over from png to webp. You can find information on doing both of those here.

[rametta]

@skyace65 I've downsized the images and converted to webp. Cheers!

[skyace65]

What did you use when scaling the images down and converting to webp? There's a noticeable amount of compression artifacts in those images.

[rametta]

I used Squoosh. I think I downsized too far before. I've redid it, and re-pushed. Should be good now.

[skyace65]

Sorry to ask for another change but could you do the images again and use the lossless compression for Squoosh. There's still very slight artifacts in the images. I talked with another maintainer and going forward we'll probably ask for lossless compression unless it's a over 300KB file. I'm making a PR for the image guide now so that's clearer in the future.

[rametta]

@skyace65 No worries. Re-pushed with lossless 🙂

[skyace65]

Thanks for the fixes! And congrats on your first merged PR!