fix task losting isssue (#665)

### What problem does this PR solve?


### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

api/db/services/llm_service.py

         else:
             assert False, "LLM type error"
 
-        num = cls.model.update(used_tokens=cls.model.used_tokens + used_tokens)\
-            .where(cls.model.tenant_id == tenant_id, cls.model.llm_name == mdlnm)\
-            .execute()
+        num = 0
+        for u in cls.query(tenant_id = tenant_id, llm_name=mdlnm):
+            num += cls.model.update(used_tokens = u.used_tokens + used_tokens)\
+                .where(cls.model.tenant_id == tenant_id, cls.model.llm_name == mdlnm)\
+                .execute()
         return num
 
 

api/db/services/task_service.py

     else:
         tsks.append(new_task())
 
-    for t in tsks:
-        REDIS_CONN.queue_product(SVR_QUEUE_NAME, message=t)
-
     bulk_insert_into_db(Task, tsks, True)
     DocumentService.begin2parse(doc["id"])
+
+    for t in tsks:
+        REDIS_CONN.queue_product(SVR_QUEUE_NAME, message=t)