fix(room): include display_name in RoomMessageEnvelope for AI streaming

RoomMessageEvent was losing the AI model name because the
From<RoomMessageEnvelope> impl hardcoded display_name: None.
Add display_name to RoomMessageEnvelope and propagate it through
all AI streaming code paths (chat, ReAct, non-streaming).
Member messages keep display_name: None.

libs/queue/types.rs

@@ -19,6 +19,9 @@ pub struct RoomMessageEnvelope {
     pub content_type: String,
     pub send_at: DateTime<Utc>,
     pub seq: i64,
+    /// Pre-resolved display name for the sender (e.g. AI model name).
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub display_name: Option<String>,
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
@@ -75,7 +78,7 @@ impl From<RoomMessageEnvelope> for RoomMessageEvent {
             content_type: e.content_type,
             send_at: e.send_at,
             seq: e.seq,
-            display_name: None,
+            display_name: e.display_name,
             reactions: None,
             message_id: None,
         }
@@ -102,6 +105,8 @@ pub struct RoomMessageStreamChunkEvent {
     pub error: Option<String>,
     /// Human-readable AI model name (e.g. "Claude 3.5 Sonnet") for display.
     pub display_name: Option<String>,
+    /// What kind of content this chunk contains: "thinking", "answer", "tool_call", "tool_result".
+    pub chunk_type: Option<String>,
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize)]

libs/room/src/message.rs

@@ -177,6 +177,7 @@ impl RoomService {
             content_type: content_type_str.clone(),
             send_at: now,
             seq,
+            display_name: None,
         };
 
         let db = &self.db;

libs/room/src/service.rs

@@ -28,7 +28,8 @@ const DEFAULT_MAX_CONCURRENT_WORKERS: usize = 1024;
 /// Callback type for sending push notifications.
 /// The caller (AppService) provides this to RoomService so it can trigger
 /// browser push notifications without depending on the service crate directly.
-pub type PushNotificationFn = Arc<dyn Fn(Uuid, String, Option<String>, Option<String>) + Send + Sync>;
+pub type PushNotificationFn =
+    Arc<dyn Fn(Uuid, String, Option<String>, Option<String>) + Send + Sync>;
 
 /// Legacy: <user>uuid</user> or <user>username</user>
 static USER_MENTION_RE: LazyLock<regex_lite::Regex, fn() -> regex_lite::Regex> =
@@ -116,7 +117,11 @@ impl RoomService {
         // Save a clone for task subscriber handles before `project_ids` gets moved.
         let task_project_ids = project_ids.clone();
 
-        tracing::info!(room_count = room_ids.len(), project_count = project_ids.len(), "starting room workers");
+        tracing::info!(
+            room_count = room_ids.len(),
+            project_count = project_ids.len(),
+            "starting room workers"
+        );
 
         let persist_fn: PersistFn = make_persist_fn(
             self.db.clone(),
@@ -133,13 +138,7 @@ impl RoomService {
             let get_redis = get_redis.clone();
             let persist_fn = persist_fn.clone();
             async move {
-                queue::start_worker(
+                queue::start_worker(worker_room_ids, get_redis, persist_fn, worker_shutdown).await;
-                    worker_room_ids,
-                    get_redis,
-                    persist_fn,
-                    worker_shutdown,
-                )
-                .await;
             }
         });
 
@@ -761,11 +760,7 @@ impl RoomService {
     /// - use_exact = false → respond to every text message.
     /// - use_exact = true → only respond when the message contains an @[ai:...] or
     ///   <mention type="ai">... tag that mentions this room's configured AI model.
-    pub async fn should_ai_respond(
+    pub async fn should_ai_respond(&self, room_id: Uuid, content: &str) -> Result<bool, RoomError> {
-        &self,
-        room_id: Uuid,
-        content: &str,
-    ) -> Result<bool, RoomError> {
         use models::rooms::room_ai;
 
         let ai_config = room_ai::Entity::find()
@@ -1046,6 +1041,12 @@ impl RoomService {
                     // Clone display_name INSIDE the async block so the outer closure stays `Fn`.
                     let ai_display_name_for_chunk = ai_display_name_for_chunk.clone();
                     async move {
+                        let chunk_type_str = match chunk.chunk_type {
+                            agent::chat::AiChunkType::Thinking => "thinking",
+                            agent::chat::AiChunkType::Answer => "answer",
+                            agent::chat::AiChunkType::ToolCall => "tool_call",
+                            agent::chat::AiChunkType::ToolResult => "tool_result",
+                        };
                         let event = RoomMessageStreamChunkEvent {
                             message_id: streaming_msg_id,
                             room_id,
@@ -1053,6 +1054,7 @@ impl RoomService {
                             done: chunk.done,
                             error: None,
                             display_name: Some(ai_display_name_for_chunk),
+                            chunk_type: Some(chunk_type_str.to_string()),
                         };
                         room_manager.broadcast_stream_chunk(event).await;
 
@@ -1091,6 +1093,7 @@ impl RoomService {
                         send_at: now,
                         seq,
                         in_reply_to: None,
+                        display_name: Some(ai_display_name_for_final.clone()),
                     };
 
                     if let Err(e) = queue.publish(room_id_inner, envelope).await {
@@ -1152,6 +1155,7 @@ impl RoomService {
                         done: true,
                         error: Some(e.to_string()),
                         display_name: Some(ai_display_name.clone()),
+                        chunk_type: None,
                     };
                     room_manager.broadcast_stream_chunk(event).await;
                 }
@@ -1376,17 +1380,15 @@ impl RoomService {
                             format!("[Thinking] {}", thought)
                         }
                         ReactStep::Action { step: _, action } => {
-                            format!(
+                            format!("[Action] Calling `{}` with {:?}", action.name, action.args)
-                                "[Action] Calling `{}` with {:?}",
-                                action.name, action.args
-                            )
                         }
-                        ReactStep::Observation { step: _, observation } => {
+                        ReactStep::Observation {
+                            step: _,
+                            observation,
+                        } => {
                             format!("[Observation] {}", observation)
                         }
-                        ReactStep::Answer { step: _, answer } => {
+                        ReactStep::Answer { step: _, answer } => answer.clone(),
-                            answer.clone()
-                        }
                     };
 
                     let is_answer = matches!(&step, ReactStep::Answer { .. });
@@ -1408,6 +1410,11 @@ impl RoomService {
                             done,
                             error: None,
                             display_name: Some((*ai_name).clone()),
+                            chunk_type: Some(if is_answer {
+                                "answer".to_string()
+                            } else {
+                                "thinking".to_string()
+                            }),
                         };
                         room_manager.broadcast_stream_chunk(event).await;
 
@@ -1423,9 +1430,7 @@ impl RoomService {
                 }
             };
 
-            let result = chat_service
+            let result = chat_service.process_react(&request, on_step).await;
-                .process_react(&request, on_step)
-                .await;
 
             let final_content = answer_buffer.lock().unwrap().clone();
             let reasoning_chain = reasoning_buffer.lock().unwrap().clone();
@@ -1454,7 +1459,8 @@ impl RoomService {
                 format!(
                     "{}\n[Error during reasoning: {}]",
                     content_to_persist.trim_end(),
-                    msg.trim_start_matches("[Agent error: ").trim_end_matches("]")
+                    msg.trim_start_matches("[Agent error: ")
+                        .trim_end_matches("]")
                 )
             } else {
                 content_to_persist
@@ -1482,6 +1488,7 @@ impl RoomService {
                 send_at: now,
                 seq,
                 in_reply_to: None,
+                display_name: Some(ai_display_name.clone()),
             };
 
             if let Err(e) = queue.publish(room_id_inner, envelope).await {
@@ -1567,6 +1574,7 @@ impl RoomService {
             send_at: now,
             seq,
             in_reply_to: None,
+            display_name: model_display_name.clone(),
         };
 
         queue.publish(room_id, envelope).await?;