fix: validate firearmId is present before constructing ModificationRequest

src/main/java/com/onixbyte/deltaforceguide/service/WebhookService.java

@@ -6,7 +6,9 @@ import com.onixbyte.deltaforceguide.manager.WebhookManager;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.data.redis.core.RedisTemplate;
+import org.springframework.http.HttpStatus;
 import org.springframework.stereotype.Service;
+import org.springframework.web.server.ResponseStatusException;
 import org.yaml.snakeyaml.Yaml;
 
 import java.time.Duration;
@@ -109,6 +111,10 @@ public class WebhookService {
         Long firearmId = modificationManager.resolveFirearmId(
                 toLong(data.get("firearmId")),
                 (String) data.get("firearmName"));
+        if (firearmId == null) {
+            throw new ResponseStatusException(HttpStatus.BAD_REQUEST,
+                    "YAML must contain firearmId or firearmName");
+        }
         String name = (String) data.get("name");
         String code = (String) data.get("code");
         List<String> tags = toStringList(data.get("tags"));