袁聪的第三次提交，API接口完善

app/service/model_gateway.py

@@ -1,7 +1,7 @@
 import os
 from collections.abc import Mapping
 from dataclasses import dataclass
-from typing import Any, Protocol
+from typing import Any, Protocol, cast
 
 import httpx
 from sqlalchemy import select
@@ -148,14 +148,18 @@ class DatabaseModelGateway:
 
     async def generate(self, *, endpoint_code: str, prompt: str, timeout_ms: int) -> str:
         endpoint = await self._endpoint(endpoint_code)
-        adapter = OpenAICompatibleGateway({endpoint.endpoint_code: endpoint})
+        adapter = OpenAICompatibleGateway(
+            {endpoint.endpoint_code: cast(EndpointSettings, endpoint)}
+        )
         return await adapter.generate(
             endpoint_code=endpoint.endpoint_code, prompt=prompt, timeout_ms=timeout_ms
         )
 
     async def embed(self, *, endpoint_code: str, text: str, timeout_ms: int) -> list[float]:
         endpoint = await self._endpoint(endpoint_code)
-        adapter = OpenAICompatibleGateway({endpoint.endpoint_code: endpoint})
+        adapter = OpenAICompatibleGateway(
+            {endpoint.endpoint_code: cast(EndpointSettings, endpoint)}
+        )
         return await adapter.embed(
             endpoint_code=endpoint.endpoint_code, text=text, timeout_ms=timeout_ms
         )