style-fix, comment improvement and codacy suggestion

Signed-off-by: Alfredo Gutierrez Grajeda <alfredo@hashgraph.com>

Author: AlfredoG87

block-node/backfill/src/main/java/org/hiero/block/node/backfill/client/BlockNodeClient.java

@@ -15,6 +15,7 @@
 public class BlockNodeClient {
     // Options definition for all gRPC services in the block node client
     private record Options(Optional<String> authority, String contentType) implements ServiceInterface.RequestOptions {}
+
     private static final BlockNodeClient.Options OPTIONS =
             new BlockNodeClient.Options(Optional.empty(), ServiceInterface.RequestOptions.APPLICATION_GRPC);
 

block-node/backfill/src/main/java/org/hiero/block/node/backfill/client/BlockStreamSubscribeUnparsedClient.java

@@ -129,10 +129,8 @@ public void onSubscribe(Flow.Subscription subscription) {
      * If the last item is a block proof, it finalizes the current block,
      * adds it to the reply list,
      * and resets the current block items and number for the next block.
-     * If the response contains a status code,
-     * it sets the error reference if the code indicates an error.
-     * If the response does not contain block items or a status code,
-     * it sets an error indicating an unexpected response.
+     * If the response contains a status code, different from SUCCESS,
+     * it sets the error reference accordingly.
      * @param subscribeStreamResponse the response to process
      */
     @Override
@@ -213,7 +211,7 @@ public void onComplete() {
 
     private static Codec<SubscribeStreamRequest> getSubscribeStreamRequestCodec(
             @NonNull final ServiceInterface.RequestOptions options) {
-        Objects.requireNonNull(options);
+        requireNonNull(options);
 
         // Default to protobuf, and don't error out if both are set:
         if (options.isJson() && !options.isProtobuf()) {