修复审批前思考过程的阶段归属

在用户回合边界立即绑定上一轮 reasoning 到对应 assistant 消息

新增审批边界回归测试，防止思考过程错误堆积到下一阶段底部

apps/ai-game-creator-shell/src-tauri/src/agent/design_runtime.rs

@@ -150,14 +150,26 @@ fn persisted_design_reasoning_entries(session: &DesignSession) -> Vec<DesignReas
     let mut group_index = 0;
     let mut assistant_index = 0;
     let mut sequence = 0_u64;
-    let mut current_reasoning = Vec::new();
-    let mut pending_reasoning = Vec::new();
+    let mut current_reasoning: Vec<DesignReasoningEntry> = Vec::new();
+    let mut pending_reasoning: Vec<DesignReasoningEntry> = Vec::new();
     let mut saw_response_output = false;
 
     for item in &session.history {
         if item.get("role").and_then(Value::as_str) == Some("user") {
             if !pending_reasoning.is_empty() || !current_reasoning.is_empty() {
                 pending_reasoning.append(&mut current_reasoning);
+                // A user item closes the previous turn. Resolve its reasoning
+                // against that turn's last assistant message before moving to
+                // the next group; otherwise it is incorrectly attached to the
+                // next turn and rendered at the bottom as an orphan.
+                let assistant_id = assistant_groups
+                    .get(group_index)
+                    .and_then(|ids| ids.last())
+                    .cloned();
+                for mut entry in pending_reasoning.drain(..) {
+                    entry.message_id = assistant_id.clone();
+                    entries.push(entry);
+                }
             }
             group_index += 1;
             assistant_index = 0;
@@ -1638,6 +1650,53 @@ mod tests {
         );
     }
 
+    #[test]
+    fn persisted_reasoning_stays_with_the_turn_before_an_approval_boundary() {
+        let mut session = new_design_session("project", "quality");
+        session.messages = vec![
+            DesignMessage {
+                id: "turn-1:user".into(),
+                role: "user".into(),
+                text: "第一轮需求".into(),
+            },
+            DesignMessage {
+                id: "turn-1:assistant".into(),
+                role: "assistant".into(),
+                text: "第一轮已提交审批".into(),
+            },
+            DesignMessage {
+                id: "turn-2:user".into(),
+                role: "user".into(),
+                text: "用户已批准，进入下一阶段".into(),
+            },
+            DesignMessage {
+                id: "turn-2:assistant".into(),
+                role: "assistant".into(),
+                text: "查询工作阶段".into(),
+            },
+        ];
+        session.history = vec![
+            json!({"role":"user", "content":"第一轮需求"}),
+            json!({"type":"reasoning", "id":"before-approval", "content":[{"type":"reasoning_text", "text":"审批前的思考"}]}),
+            json!({"type":"message", "role":"assistant", "content":[{"type":"output_text", "text":"第一轮已提交审批"}]}),
+            json!({"role":"user", "content":"用户已批准，进入下一阶段"}),
+            json!({"type":"reasoning", "id":"after-approval", "content":[{"type":"reasoning_text", "text":"审批后的思考"}]}),
+            json!({"type":"message", "role":"assistant", "content":[{"type":"output_text", "text":"查询工作阶段"}]}),
+        ];
+
+        let entries = persisted_design_reasoning_entries(&session);
+        assert_eq!(
+            entries
+                .iter()
+                .map(|entry| (entry.id.as_str(), entry.message_id.as_deref()))
+                .collect::<Vec<_>>(),
+            vec![
+                ("before-approval", Some("turn-1:assistant")),
+                ("after-approval", Some("turn-2:assistant")),
+            ]
+        );
+    }
+
     #[tokio::test(flavor = "current_thread")]
     async fn scripted_design_provider_emits_reasoning_without_persisting_it() {
         let (_temp, root, _resources) = init_design_project();