dev add new action

src/main/java/ru/soune/nocopy/service/violation/ViolationService.java

@@ -56,6 +56,10 @@ public class ViolationService {
         }
     }
 
+    public Violation getById(Long violationId) {
+        return violationRepository.findById(violationId).orElse(null);
+    }
+
     public List<FileViolationSummaryDTO> getFileViolationsSummary(Long userId) {
         List<FileEntity> userFiles = fileEntityService.getAllUserFiles(userId);
         List<Violation> violations = violationRepository.findByFileEntityIn(userFiles);