chore: added StringMapValue to config system

common/src/main/java/dev/ftb/mods/ftblibrary/snbt/config/StringMapValue.java

@@ -0,0 +1,37 @@
+package dev.ftb.mods.ftblibrary.snbt.config;
+
+import dev.ftb.mods.ftblibrary.snbt.SNBTCompoundTag;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class StringMapValue extends BaseValue<Map<String, String>> {
+    public StringMapValue(@Nullable SNBTConfig c, String n, Map<String, String> def) {
+        super(c, n, def);
+        super.set(new HashMap<>(def));
+    }
+
+    @Override
+    public void write(SNBTCompoundTag tag) {
+        Map<String, String> map = get();
+        SNBTCompoundTag mapTag = new SNBTCompoundTag();
+
+        for (Map.Entry<String, String> entry : map.entrySet()) {
+            mapTag.putString(entry.getKey(), entry.getValue());
+        }
+
+        tag.put(key, mapTag);
+    }
+
+    @Override
+    public void read(SNBTCompoundTag tag) {
+        Map<String, String> map = new HashMap<>();
+
+        for (String key : tag.getAllKeys()) {
+            map.put(key, tag.getString(key));
+        }
+
+        set(map);
+    }
+}