Implement give item & Implement configurable handbook endpoints

src/main/java/emu/grasscutter/utils/objects/HandbookBody.java

@@ -4,6 +4,7 @@ import lombok.Builder;
 import lombok.Getter;
 
 /** HTTP request object for handbook controls. */
+@SuppressWarnings("FieldMayBeFinal")
 public interface HandbookBody {
     @Builder
     class Response {
@@ -20,4 +21,12 @@ public interface HandbookBody {
         private int constellations = 6; // Range between 0 - 6.
         private int talentLevels = 10; // Range between 1 - 15.
     }
+
+    @Getter
+    class GiveItem {
+        private String player; // Parse into online player ID.
+        private String item; // Parse into item ID.
+
+        private int amount = 1; // Range between 1 - Long.MAX_VALUE.
+    }
 }