Create files from Grasscutter-Quests

these files are NOT directly compatible with Grasscutter, and require additional modifications to the codebase to work.

src/main/java/emu/grasscutter/game/quest/QuestValueExec.java

@@ -0,0 +1,11 @@
+package emu.grasscutter.game.quest;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
+import emu.grasscutter.game.quest.enums.QuestExec;
+
+@Retention(RetentionPolicy.RUNTIME)
+public @interface QuestValueExec {
+    QuestExec value();
+}