feat - 배너 api 응답값에 배경색 정보 추가

src/main/java/sopt/org/hmh/domain/banner/Banner.java

@@ -22,4 +22,5 @@ public class Banner {
     private String subTitle;
     private String imageUrl;
     private String linkUrl;
+    private String backgroundColors;
 }

src/main/java/sopt/org/hmh/domain/banner/BannerResponse.java

@@ -2,19 +2,30 @@
 
 import lombok.Builder;
 
+import java.util.Arrays;
+import java.util.List;
+
 @Builder
 public record BannerResponse(
         String title,
         String subTitle,
         String imageUrl,
-        String linkUrl
+        String linkUrl,
+        List<String> backgroundColors
+
 ) {
     public static BannerResponse of(Banner banner) {
         return BannerResponse.builder()
                 .title(banner.getTitle())
                 .subTitle(banner.getSubTitle())
                 .imageUrl(banner.getImageUrl())
                 .linkUrl(banner.getLinkUrl())
+                .backgroundColors(convertToColorArray(banner.getBackgroundColors()))
                 .build();
     }
+
+    private static List<String> convertToColorArray(String input) {
+        String[] colorArray = input.split(",\\s*");
+        return Arrays.asList(colorArray);
+    }
 }