refactor: optimize provider query and stats aggregation logic

src/api/handlers/base/chat_handler_base.py

@@ -266,8 +266,11 @@ class ChatHandlerBase(BaseMessageHandler, ABC):
         if mapping and mapping.model:
             # 使用 select_provider_model_name 支持别名功能
             # 传入 api_key.id 作为 affinity_key，实现相同用户稳定选择同一别名
+            # 传入 api_format 用于过滤适用的别名作用域
             affinity_key = self.api_key.id if self.api_key else None
-            mapped_name = mapping.model.select_provider_model_name(affinity_key)
+            mapped_name = mapping.model.select_provider_model_name(
+                affinity_key, api_format=self.FORMAT_ID
+            )
             logger.debug(f"[Chat] 模型映射: {source_model} -> {mapped_name}")
             return mapped_name