Fixs for translation agent (#3557)

### What problem does this PR solve?

#3556 

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)
- [x] New Feature (non-breaking change which adds functionality)

api/apps/canvas_app.py

@@ -120,7 +120,10 @@ def run():
             try:
                 for ans in canvas.run(stream=True):
                     if ans.get("running_status"):
-                        yield "data:" + json.dumps({"code": 0, "message": "", "data": ans}, ensure_ascii=False) + "\n\n"
+                        yield "data:" + json.dumps({"code": 0, "message": "",
+                                                    "data": {"answer": ans["content"],
+                                                             "running_status": True}},
+                                                   ensure_ascii=False) + "\n\n"
                         continue
                     for k in ans.keys():
                         final_ans[k] = ans[k]

api/apps/user_app.py

@@ -518,6 +518,7 @@ def user_register(user_id, user):
                 "model_type": llm.model_type,
                 "api_key": settings.API_KEY,
                 "api_base": settings.LLM_BASE_URL,
+                "max_tokens": llm.max_tokens
             }
         )