fix: client sse (#177)

fix client send stream message without set text/event-stream.

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Fixes #<issue_number_goes_here> 🦕

---------

Co-authored-by: chenkangqiang <[email protected]>

Author: ChenKangQiang

client/src/main/java/io/a2a/http/JdkA2AHttpClient.java

@@ -141,7 +141,7 @@ public CompletableFuture<Void> getAsyncSSE(
                 Consumer<String> messageConsumer,
                 Consumer<Throwable> errorConsumer,
                 Runnable completeRunnable) throws IOException, InterruptedException {
-            HttpRequest request = createRequestBuilder(false)
+            HttpRequest request = createRequestBuilder(true)
                     .build();
             return super.asyncRequest(request, messageConsumer, errorConsumer, completeRunnable);
         }
@@ -180,7 +180,7 @@ public CompletableFuture<Void> postAsyncSSE(
                 Consumer<String> messageConsumer,
                 Consumer<Throwable> errorConsumer,
                 Runnable completeRunnable) throws IOException, InterruptedException {
-            HttpRequest request = createRequestBuilder(false)
+            HttpRequest request = createRequestBuilder(true)
                     .build();
             return super.asyncRequest(request, messageConsumer, errorConsumer, completeRunnable);
         }