feat: Add OpenAI-compatible provider nodes

- Support multiple OpenAI-compatible providers with custom prefix/baseUrl
- Add provider nodes CRUD (create/read/update/delete)
- URL building: baseUrl + /chat/completions or /responses
- Model import from /models endpoint
- API key validation via /models
- Usage type safety across all translators
- OAuth token auto-refresh for expired tokens

src/models/index.js

@@ -5,6 +5,12 @@ export {
   createProviderConnection,
   updateProviderConnection,
   deleteProviderConnection,
+  getProviderNodes,
+  getProviderNodeById,
+  createProviderNode,
+  updateProviderNode,
+  deleteProviderNode,
+  deleteProviderConnectionsByProvider,
   getModelAliases,
   setModelAlias,
   deleteModelAlias,