🔐 feat: Implement Entra ID authentication for Azure OpenAI integration

- Added support for Entra ID authentication in OpenAIClient and related services.
- Updated header management to conditionally use Entra ID access tokens or API keys based on environment configuration.
- Introduced utility functions for Entra ID token retrieval and credential management.
- Enhanced tests to verify Entra ID authentication flow and its integration with Azure configurations.

packages/api/src/endpoints/openai/initialize.ts

@@ -6,7 +6,7 @@ import type {
   UserKeyValues,
 } from '~/types';
 import { createHandleLLMNewToken } from '~/utils/generators';
-import { getAzureCredentials } from '~/utils/azure';
+import { getAzureCredentials, getEntraIdAccessToken, shouldUseEntraId } from '~/utils/azure';
 import { isUserProvided } from '~/utils/common';
 import { resolveHeaders } from '~/utils/env';
 import { getOpenAIConfig } from './config';
@@ -110,12 +110,30 @@ export const initializeOpenAI = async ({
       if (!clientOptions.headers) {
         clientOptions.headers = {};
       }
-      clientOptions.headers['api-key'] = apiKey;
+      if (shouldUseEntraId()) {
+        clientOptions.headers['Authorization'] = `Bearer ${await getEntraIdAccessToken()}`;
+      } else {
+        clientOptions.headers['api-key'] = apiKey || '';
+      }
+    } else {
+      apiKey = azureOptions.azureOpenAIApiKey || '';
+      clientOptions.azure = azureOptions;
+      if (shouldUseEntraId()) {
+        apiKey = 'entra-id-placeholder';
+        clientOptions.headers['Authorization'] = `Bearer ${await getEntraIdAccessToken()}`;
+      }
     }
   } else if (isAzureOpenAI) {
     clientOptions.azure =
       userProvidesKey && userValues?.apiKey ? JSON.parse(userValues.apiKey) : getAzureCredentials();
-    apiKey = clientOptions.azure ? clientOptions.azure.azureOpenAIApiKey : undefined;
+    if (shouldUseEntraId()) {
+      clientOptions.headers = {
+        ...clientOptions.headers,
+        Authorization: `Bearer ${await getEntraIdAccessToken()}`,
+      };
+    } else {
+      apiKey = clientOptions.azure ? clientOptions.azure.azureOpenAIApiKey : undefined;
+    }
   }
 
   if (userProvidesKey && !apiKey) {