Port to Architectury

Yes, that also means Forge!
And yes, this was pain.
And no, the file size has not increased much!

common/src/main/resources/midnightlib.mixins.json

@@ -0,0 +1,13 @@
+{
+  "required": true,
+  "minVersion": "0.8",
+  "package": "eu.midnightdust.core.mixin",
+  "compatibilityLevel": "JAVA_17",
+  "client": [
+    "MixinOptionsScreen",
+    "MixinPlayerEntityRenderer"
+  ],
+  "injectors": {
+    "defaultRequire": 1
+  }
+}