🌉 fix: Add Proxy Support to Gemini Image Gen Tool (#11302)

* ✨ feat: Add proxy support for Google APIs in GeminiImageGen

- Implemented a proxy wrapper for globalThis.fetch to route requests to googleapis.com through a specified proxy.
- Added tests to verify the proxy configuration behavior, ensuring correct dispatcher application for Google API calls and preserving existing options.

Co-authored-by: [Your Name] <your.email@example.com>

* chore: remove comment

---------

Co-authored-by: [Your Name] <your.email@example.com>
Co-authored-by: Danny Avila <danacordially@gmail.com>

api/app/clients/tools/structured/GeminiImageGen.js

@@ -2,6 +2,7 @@ const fs = require('fs');
 const path = require('path');
 const sharp = require('sharp');
 const { v4 } = require('uuid');
+const { ProxyAgent } = require('undici');
 const { GoogleGenAI } = require('@google/genai');
 const { tool } = require('@langchain/core/tools');
 const { logger } = require('@librechat/data-schemas');
@@ -21,6 +22,24 @@ const { getStrategyFunctions } = require('~/server/services/Files/strategies');
 const { spendTokens } = require('~/models/spendTokens');
 const { getFiles } = require('~/models/File');
 
+/**
+ * Configure proxy support for Google APIs
+ * This wraps globalThis.fetch to add a proxy dispatcher only for googleapis.com URLs
+ * This is necessary because @google/genai SDK doesn't support custom fetch or httpOptions.dispatcher
+ */
+if (process.env.PROXY) {
+  const originalFetch = globalThis.fetch;
+  const proxyAgent = new ProxyAgent(process.env.PROXY);
+
+  globalThis.fetch = function (url, options = {}) {
+    const urlString = url.toString();
+    if (urlString.includes('googleapis.com')) {
+      options = { ...options, dispatcher: proxyAgent };
+    }
+    return originalFetch.call(this, url, options);
+  };
+}
+
 /**
  * Get the default service key file path (consistent with main Google endpoint)
  * @returns {string} - The default path to the service key file