Created NPC types and created the config needed to load them

src/main/java/com/alttd/fishingevent/util/NPCCreateData.java

@@ -0,0 +1,7 @@
+package com.alttd.fishingevent.util;
+
+import org.bukkit.Material;
+import org.jetbrains.annotations.Nullable;
+
+public record NPCCreateData(Skin skin, String simpleId, String name, @Nullable Material mainHand, @Nullable Material offHand) {
+}

src/main/java/com/alttd/fishingevent/util/Skin.java

@@ -0,0 +1,5 @@
+package com.alttd.fishingevent.util;
+
+public record Skin(String texture, String signature) {
+
+}