feat: add result change log entities

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

@@ -23,7 +23,7 @@ public abstract class PostChangeLog {
     @JoinColumn(name = "post_id")
     private Post post;
 
-    @ManyToOne(fetch = FetchType.LAZY, optional = false)
+    @ManyToOne(fetch = FetchType.LAZY, optional = true)
     @JoinColumn(name = "user_id")
     private User user;
 

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

@@ -7,5 +7,7 @@ public enum PostChangeType {
     TAG,
     CLOSED,
     PINNED,
-    FEATURED
+    FEATURED,
+    VOTE_RESULT,
+    LOTTERY_RESULT
 }

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

@@ -0,0 +1,16 @@
+package com.openisle.model;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.Table;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+@Getter
+@Setter
+@NoArgsConstructor
+@Entity
+@Table(name = "post_lottery_result_change_logs")
+public class PostLotteryResultChangeLog extends PostChangeLog {
+}
+

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

@@ -0,0 +1,16 @@
+package com.openisle.model;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.Table;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+@Getter
+@Setter
+@NoArgsConstructor
+@Entity
+@Table(name = "post_vote_result_change_logs")
+public class PostVoteResultChangeLog extends PostChangeLog {
+}
+