feat(db): 添加 Ollama本地离线模型支持

- 在 builtin_providers.json 中添加 Ollama 提供商配置
- 修改 OpenAI_compatible_provider.py，优化与 Ollama 的兼容性

backend/app/db/builtin_providers.json

@@ -46,5 +46,13 @@
     "logo": "Groq",
     "api_key": "",
     "base_url": "https://api.groq.com/openai/v1"
+  },
+      {
+    "id": "ollama",
+    "name": "ollama",
+    "type": "built-in",
+    "logo": "Ollama",
+    "api_key": "",
+    "base_url": "http://127.0.0.1:11434/v1"
   }
 ]

backend/app/gpt/provider/OpenAI_compatible_provider.py

@@ -16,7 +16,6 @@ class OpenAICompatibleProvider:
         print(api_key)
         try:
             client = OpenAI(api_key=api_key, base_url=base_url)
-
             client.models.list()
             return True
         except Exception as e: