Few improvements such as

application.properties.prod file
new DTO for response when adding notice

src/main/resources/application.properties

@@ -15,5 +15,5 @@ spring.jpa.defer-datasource-initialization=true
 spring.jpa.hibernate.ddl-auto=create-drop
 
 file.upload-dir=/Users/andsol/Desktop/uploads
-spring.servlet.multipart.max-file-size=5MB
-spring.servlet.multipart.max-request-size=5MB
+spring.servlet.multipart.max-file-size=10MB
+spring.servlet.multipart.max-request-size=10MB