made improvements

backend/src/main/java/com/vaessl/app/dto/ConnectionRequest.java

@@ -6,8 +6,8 @@ import jakarta.validation.constraints.NotBlank;
 import jakarta.validation.constraints.NotEmpty;
 
 public record ConnectionRequest(
-        @NotBlank(message = "App URL is mandatory") String appUrl,
-        @NotBlank String serviceType, 
-        @NotEmpty Map <String, String> credentials,
-        boolean stayLoggedIn) {
+                @NotBlank(message = "App URL is mandatory") String appUrl,
+                @NotBlank(message = "Service type is mandatory") String serviceType,
+                @NotEmpty(message = "Credentials are mandatory") Map<String, String> credentials,
+                boolean stayLoggedIn) {
 }