story-kit: merge 174_story_constrain_thinking_traces_in_chat_panel

server/src/http/ws.rs

@@ -103,6 +103,12 @@ enum WsResponse {
     /// Heartbeat response to a client `Ping`. Lets the client confirm the
     /// connection is alive and cancel any stale-connection timeout.
     Pong,
+    /// Streaming thinking token from an extended-thinking block.
+    /// Sent separately from `Token` so the frontend can render them in
+    /// a constrained, scrollable ThinkingBlock rather than inline.
+    ThinkingToken {
+        content: String,
+    },
     /// Sent on connect when the project's spec files still contain scaffold
     /// placeholder content and the user needs to go through onboarding.
     OnboardingStatus {
@@ -257,6 +263,7 @@ pub async fn ws_handler(ws: WebSocket, ctx: Data<&Arc<AppContext>>) -> impl poem
                 Ok(WsRequest::Chat { messages, config }) => {
                     let tx_updates = tx.clone();
                     let tx_tokens = tx.clone();
+                    let tx_thinking = tx.clone();
                     let tx_activity = tx.clone();
                     let ctx_clone = ctx.clone();
 
@@ -277,6 +284,11 @@ pub async fn ws_handler(ws: WebSocket, ctx: Data<&Arc<AppContext>>) -> impl poem
                                 content: token.to_string(),
                             });
                         },
+                        move |thinking: &str| {
+                            let _ = tx_thinking.send(WsResponse::ThinkingToken {
+                                content: thinking.to_string(),
+                            });
+                        },
                         move |tool_name: &str| {
                             let _ = tx_activity.send(WsResponse::ToolActivity {
                                 tool_name: tool_name.to_string(),
@@ -595,6 +607,16 @@ mod tests {
         assert_eq!(json["type"], "pong");
     }
 
+    #[test]
+    fn serialize_thinking_token_response() {
+        let resp = WsResponse::ThinkingToken {
+            content: "I need to think about this...".to_string(),
+        };
+        let json = serde_json::to_value(&resp).unwrap();
+        assert_eq!(json["type"], "thinking_token");
+        assert_eq!(json["content"], "I need to think about this...");
+    }
+
     #[test]
     fn serialize_onboarding_status_true() {
         let resp = WsResponse::OnboardingStatus {