feat: introduce MCP_PROXY_URL env var (#607)

Author: DaveHanns

packages/consts/src/consts.ts

@@ -290,6 +290,7 @@ export const APIFY_ENV_VARS = {
     PROXY_PASSWORD: 'APIFY_PROXY_PASSWORD',
     PROXY_PORT: 'APIFY_PROXY_PORT',
     PROXY_STATUS_URL: 'APIFY_PROXY_STATUS_URL',
+    MCP_PROXY_URL: 'APIFY_MCP_PROXY_URL',
     PURGE_ON_START: 'APIFY_PURGE_ON_START',
     SDK_LATEST_VERSION: 'APIFY_SDK_LATEST_VERSION',
     SYSTEM_INFO_INTERVAL_MILLIS: 'APIFY_SYSTEM_INFO_INTERVAL_MILLIS',