[Feat] 미리보기 댓글에 사진 존재 유무 필드 추가

backend/src/main/java/com/example/Piroin/project/domain/question/dto/QuestionResDTO.java

@@ -166,6 +166,8 @@ public record PreviewCommentResponse(
             Long commentId,
             String displayName,
             String content,
+            // true면 프론트는 미리보기 댓글에 "사진 보기" 버튼을 노출하고 질문 상세 페이지로 이동시킨다.
+            Boolean hasImage,
             LocalDateTime createdAt
     ) {
     }

backend/src/main/java/com/example/Piroin/project/domain/question/repository/QuestionCommentRepository.java

@@ -27,6 +27,7 @@ public interface QuestionCommentRepository extends JpaRepository<QuestionComment
                    ranked.user_id AS "userId",
                    u.role AS "userRole",
                    ranked.content AS "content",
+                   ranked.image_url AS "imageUrl",
                    ranked.created_at AS "createdAt",
                    qai.anonymous_no AS "anonymousNo"
             FROM (
@@ -80,6 +81,8 @@ interface PreviewCommentRow {
 
         String getContent();
 
+        String getImageUrl();
+
         LocalDateTime getCreatedAt();
 
         Integer getAnonymousNo();

backend/src/main/java/com/example/Piroin/project/domain/question/service/QuestionService.java

@@ -584,10 +584,15 @@ private QuestionResDTO.PreviewCommentResponse toPreviewCommentResponse(
                 row.getCommentId(),
                 getPreviewDisplayName(question, row),
                 row.getContent(),
+                hasPreviewImage(row),
                 row.getCreatedAt()
         );
     }
 
+    private boolean hasPreviewImage(QuestionCommentRepository.PreviewCommentRow row) {
+        return row.getImageUrl() != null && !row.getImageUrl().isBlank();
+    }
+
     private String getPreviewDisplayName(Question question, QuestionCommentRepository.PreviewCommentRow row) {
         if (row.getUserId().equals(question.getUser().getId())) {
             return "작성자";