Revert "minor update"

This reverts commit 29295a5.

Author: alexcheng1982

spring-ai-adapter/src/main/java/com/javaaidev/chatagent/springai/ModelAdapter.java

@@ -16,7 +16,6 @@
 import org.springframework.ai.chat.model.ChatResponse;
 import org.springframework.ai.chat.model.Generation;
 import org.springframework.http.codec.ServerSentEvent;
-import org.springframework.util.StringUtils;
 import reactor.core.publisher.Flux;
 
 /**
@@ -79,9 +78,8 @@ public static Flux<ServerSentEvent<ChatAgentResponse>> toStreamingResponse(
       Flux<ChatResponse> chatResponse) {
     return chatResponse.concatMap(
             response -> Flux.fromIterable(response.getResults()))
-        .filter(generation -> Objects.nonNull(generation.getOutput()))
+        .filter(generation -> Objects.nonNull(generation.getOutput().getText()))
         .map(generation -> generation.getOutput().getText())
-        .filter(StringUtils::hasText)
         .map(text -> ServerSentEvent.<ChatAgentResponse>builder()
             .data(new ChatAgentResponse(
                 List.of(new TextContentPart(text))))