🖥️ feat: Add Proxy Support for Tavily API Tool (#10770)

* 🖥️ feat: Add Proxy Support for Tavily API Tool

- Integrated ProxyAgent from undici to enable proxy support for API requests in TavilySearch and TavilySearchResults.
- Updated fetch options to conditionally include the proxy configuration based on the environment variable, enhancing flexibility for network requests.

* ci: TavilySearchResults with Proxy Support Tests

- Added tests to verify the integration of ProxyAgent for API requests in TavilySearchResults.
- Implemented conditional logic to check for the PROXY environment variable, ensuring correct usage of ProxyAgent based on its presence.
- Updated test setup to clear mocks before each test for improved isolation and reliability.

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

@@ -1,4 +1,5 @@
 const { z } = require('zod');
+const { ProxyAgent, fetch } = require('undici');
 const { tool } = require('@langchain/core/tools');
 const { getApiKey } = require('./credentials');
 
@@ -19,13 +20,19 @@ function createTavilySearchTool(fields = {}) {
         ...kwargs,
       };
 
-      const response = await fetch('https://api.tavily.com/search', {
+      const fetchOptions = {
         method: 'POST',
         headers: {
           'Content-Type': 'application/json',
         },
         body: JSON.stringify(requestBody),
-      });
+      };
+
+      if (process.env.PROXY) {
+        fetchOptions.dispatcher = new ProxyAgent(process.env.PROXY);
+      }
+
+      const response = await fetch('https://api.tavily.com/search', fetchOptions);
 
       const json = await response.json();
       if (!response.ok) {