feat: support featured medals

backend/src/main/java/com/openisle/model/MedalType.java

@@ -3,6 +3,7 @@ package com.openisle.model;
 public enum MedalType {
     COMMENT,
     POST,
+    FEATURED,
     CONTRIBUTOR,
     SEED,
     PIONEER

backend/src/main/java/com/openisle/model/NotificationType.java

@@ -40,6 +40,8 @@ public enum NotificationType {
     LOTTERY_WIN,
     /** Your lottery post was drawn */
     LOTTERY_DRAW,
+    /** Your post was featured */
+    POST_FEATURED,
     /** You were mentioned in a post or comment */
     MENTION
 }

backend/src/main/java/com/openisle/model/PointHistoryType.java

@@ -6,6 +6,7 @@ public enum PointHistoryType {
     POST_LIKED,
     COMMENT_LIKED,
     INVITE,
+    FEATURE,
     SYSTEM_ONLINE,
     REDEEM
 }