Replace NG use by a custom neodev plugin built on top of NFRT and MDG

[Technici4n]

This PR replaces our use of NG by a custom plugin that is based on NFRT and MDG, and lives in the buildSrc/ folder.

The main advantages are as follows:

• Make continued development of the plugin, and by extension of a lot of our toolchain, easier, by integrating it into the same repository as NeoForge itself.
  • Large changes to the Gradle setup do not require us to start a new major version of the plugin that modders are using.
• Reduce the unnecessary complexity that would come with wanting to design "DSLs" for every aspect of neodev.
• Make further experiments (binpatch changes, split sources, includeBuild for NeoForge, etc...) easier to develop and deliver.
• Thanks to NFRT, the asset folder from various launchers is reused.

TODO:

• Eclipse support
• Junit runs and our own junit tests
• Server installer
• A lot more testing!
• Big pass(es) of cleanup to simplify even more.
  • Decide how to manage versions.
  • Other cleanup.
• Integrate related MDG changes (Rework Runs and Unit Testing to be reusable from NeoDev ModDevGradle#141), and decide on a policy to keep them reasonably stable.
• Update DiffPatch to io.codechicken variant.

[neoforged-pr-publishing]

• Publish PR to GitHub Packages

Last commit published: 14807ec48523497209e756f609225f9527a0c1c7.

PR Publishing

The artifacts published by this PR:

• 📦 net.neoforged:neoforge:21.3.30-beta-pr-1485-features-moddevgradle
• 📦 net.neoforged:testframework:21.3.30-beta-pr-1485-features-moddevgradle

Repository Declaration

In order to use the artifacts published by the PR, add the following repository to your buildscript:

repositories {
    maven {
        name 'Maven for PR #1485' // https://github.com/neoforged/NeoForge/pull/1485
        url 'https://prmaven.neoforged.net/NeoForge/pr1485'
        content {
            includeModule('net.neoforged', 'neoforge')
            includeModule('net.neoforged', 'testframework')
        }
    }
}

MDK installation

In order to setup a MDK using the latest PR version, run the following commands in a terminal.
The script works on both *nix and Windows as long as you have the JDK bin folder on the path.
The script will clone the MDK in a folder named NeoForge-pr1485.
On Powershell you will need to remove the -L flag from the curl invocation.

mkdir NeoForge-pr1485
cd NeoForge-pr1485
curl -L https://prmaven.neoforged.net/NeoForge/pr1485/net/neoforged/neoforge/21.3.30-beta-pr-1485-features-moddevgradle/mdk-pr1485.zip -o mdk.zip
jar xf mdk.zip
rm mdk.zip || del mdk.zip

To test a production environment, you can download the installer from here.

[neoforged-automation]

@Technici4n, this pull request has conflicts, please resolve them for this PR to move forward.

[shartte]

Was this previously done in NG?

[Technici4n]

Looks like it wasn't necessary because the java plugin wasn't getting applied to the root project? I'm not sure why I had to apply java, I think it's for the neodev plugin. We shouldn't need the neodev plugin for the root project though.

[Technici4n]

Should probably be apply false?