feat: Update for Forge 1.21.4

forge/build.gradle

@@ -7,8 +7,6 @@ plugins {
 }
 
 mixin {
-    add(sourceSets.main, "${mod_id}.refmap.json")
-
     config("${mod_id}.mixins.json")
     config("${mod_id}.forge.mixins.json")
 }
@@ -90,4 +88,10 @@ publishing {
             fg.component(it)
         }
     }
+}
+
+sourceSets.each {
+    def dir = layout.buildDirectory.dir("sourcesSets/$it.name")
+    it.output.resourcesDir = dir
+    it.java.destinationDirectory = dir
 }

forge/src/main/java/net/blay09/mods/kuma/forge/ForgeKumaAPI.java

@@ -1,16 +1,15 @@
 package net.blay09.mods.kuma.forge;
 
-import net.minecraftforge.api.distmarker.Dist;
-import net.minecraftforge.eventbus.api.IEventBus;
 import net.minecraftforge.fml.common.Mod;
+import net.minecraftforge.fml.javafmlmod.FMLJavaModLoadingContext;
 import net.minecraftforge.fml.loading.FMLEnvironment;
 
 @Mod(value = "kuma_api")
 public class ForgeKumaAPI {
 
-    public ForgeKumaAPI(IEventBus modEventBus) {
-        if (FMLEnvironment.dist == Dist.CLIENT) {
-            ForgeKumaAPIClient.init(modEventBus);
+    public ForgeKumaAPI(FMLJavaModLoadingContext context) {
+        if (FMLEnvironment.dist.isClient()) {
+            ForgeKumaAPIClient.init(context.getModEventBus());
         }
     }
 }

forge/src/main/resources/kuma_api.forge.mixins.json

@@ -3,7 +3,6 @@
   "minVersion": "0.8",
   "package": "net.blay09.mods.kuma.mixin",
   "compatibilityLevel": "JAVA_17",
-  "refmap": "${mod_id}.refmap.json",
   "mixins": [
   ],
   "client": [