[6.x] Update FabricJS to latest

[brianjhanson]

Updates FabricJS from ^1.7 to ^6.0. Leaving this as a draft because I'm sure https://github.com/craftcms/cms/pull/17880 will cause some conflicts. I'm also running into a bug where if you straighten an image and then rotate it, the math gets off and the image doesn't rotate properly. I'm feeling like that might require a bit more of a refactor, but I don't really want to take that on until #17880 is in to the main branch.

Fixes #3122