Port to 1.21

[unilock]

This PR ports PolyForgery to 1.21(.1).

Also:

• All textures have been optimized with oxipng, making them a bit smaller
• Polydex support is still present
• Tier Override information is now visible in the Polydex recipes (i.e. higher tier Alloy Forges sometimes have a higher yield; this is now presented in the Polydex recipe)
• Various things have been cleaned up

[CamperSamu]

Thanks for the PR!
I am merging this manually ASAP rebasing on your tree, pushing everything after building and testing.

Since serverside modding is going more and more mainstream, I am also planning to ship this mod to Modrinth (after ages, I know), I'll make sure to add you as a contributor (as well as any major contributors from the past)

[unilock]

Ah, one thing I forgot to fix is that sgui needs to be jar-in-jar'd (include(...)), since it's not present in any of the dependencies of PolyForgery.

[CamperSamu]

Fixed it, thanks for the heads up
The only issue I noticed is a client failure when building the multiblock, it disconnects with "No value with id 44" so I think that PolyMc is not blocking everything correctly.
This will probably be gone when PolyMc releases since 1.21 is still WIP, so I'll ignore it for now

[CamperSamu]

Manually merged your patches and force-pushed the new up-to-date tree to the 1.21.1 branch, thanks again!

[CamperSamu]

Release out on GitHub: v2.1.0+1.21.1 - Update to 1.21.1, Compressed Textures and Polydex is back!
Waiting for TheEpicBlock/PolyMc v5.7.0 for the Modrinth release