added create_datapack, check_hidden_dimensions and world_dimensions in system info.

src/main/java/carpet/mixins/ReloadCommand_reloadAppsMixin.java

@@ -0,0 +1,23 @@
+package carpet.mixins;
+
+import carpet.CarpetServer;
+import com.mojang.brigadier.context.CommandContext;
+import net.minecraft.server.command.ReloadCommand;
+import net.minecraft.server.command.ServerCommandSource;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
+
+@Mixin(ReloadCommand.class)
+public class ReloadCommand_reloadAppsMixin {
+    //method_13530(Lcom/mojang/brigadier/context/CommandContext;)I
+    // internal of register.
+    @SuppressWarnings("UnresolvedMixinReference")
+    @Inject(method = "method_13530", at = @At("TAIL"))
+    private static void onReload(CommandContext<ServerCommandSource> context, CallbackInfoReturnable<Integer> cir)
+    {
+        // can't fetch here the reference to the server
+        CarpetServer.onReload(context.getSource().getMinecraftServer());
+    }
+}