fix(streaming): use repeat_with + take for [DONE] marker

src/server/mod.rs

@@ -246,7 +246,7 @@ async fn chat_completions(
                 let stream_id = format!("chatcmpl-{}", Uuid::new_v4());
                 let stream_created = chrono::Utc::now().timestamp() as u64;
                 
-                // Create the SSE event stream
+                // Map chunks to SSE events
                 let sse_stream = aggregating_stream
                     .map(move |chunk_result| {
                         match chunk_result {
@@ -274,10 +274,9 @@ async fn chat_completions(
                         }
                     });
 
-                // Chain [DONE] event - this should work now with the corrected stream type
-                let done_stream = futures::stream::once(async {
-                    Ok::<Event, AppError>(Event::default().data("[DONE]"))
-                });
+                // Chain [DONE] - using repeat_with to ensure it gets polled
+                let done_stream = futures::stream::repeat_with(|| Ok::<Event, AppError>(Event::default().data("[DONE]")))
+                    .take(1);
                 let out = sse_stream.chain(done_stream);
 
                 Ok(Sse::new(out).into_response())