refactor : board name 출력 변경

backend/src/main/java/com/edufocus/edufocus/board/entity/vo/Board.java

@@ -62,7 +62,7 @@ public class Board {
         return ResponseBoardSummaryDto.builder()
                 .id(id)
                 .title(title)
-                .name(user.getUserId())
+                .name(user.getName())
                 .createdAt(createdAt)
                 .build();
     }

backend/src/main/java/com/edufocus/edufocus/board/entity/vo/Comment.java

@@ -42,7 +42,7 @@ public class Comment {
     public ResponseCommentDto makeCommentDto() {
         return ResponseCommentDto.builder()
                 .id(id)
-                .name(user.getEmail())
+                .name(user.getName())
                 .content(content)
                 .createAt(createdAt)
                 .modifiedAt(modifiedAt)