added chats with another users

src/main/java/com/krylov/refound/entity/Message.java

@@ -6,6 +6,7 @@ import jakarta.persistence.GeneratedValue;
 import jakarta.persistence.GenerationType;
 import jakarta.persistence.Id;
 import jakarta.persistence.ManyToOne;
+import jakarta.persistence.PrePersist;
 import jakarta.persistence.Table;
 import java.time.LocalDateTime;
 import lombok.Getter;
@@ -20,16 +21,23 @@ public class Message {
   @GeneratedValue(strategy = GenerationType.IDENTITY)
   private Long id;
 
-  @ManyToOne
-  private User sender;
+  @Column(name = "chat_id", nullable = false)
+  private Long chatId;
 
-  @ManyToOne
-  private User receiver;
+  @Column(name = "sender_id", nullable = false)
+  private Long senderId;
 
-  @Column(length = 2000)
+  @Column(nullable = false, columnDefinition = "TEXT")
   private String content;
 
+  @Column(name = "is_read", nullable = false)
+  private boolean isRead = false;
+
+  @Column(name = "created_at", nullable = false)
   private LocalDateTime createdAt;
 
-  private boolean isRead;
+  @PrePersist
+  protected void onCreate() {
+    createdAt = LocalDateTime.now();
+  }
 }