Models: add Vercel AI Gateway auth

src/commands/onboard-auth.ts

@@ -10,6 +10,8 @@ export {
   applyOpenrouterProviderConfig,
   applySyntheticConfig,
   applySyntheticProviderConfig,
+  applyVercelAiGatewayConfig,
+  applyVercelAiGatewayProviderConfig,
   applyZaiConfig,
 } from "./onboard-auth.config-core.js";
 export {
@@ -34,8 +36,10 @@ export {
   setOpencodeZenApiKey,
   setOpenrouterApiKey,
   setSyntheticApiKey,
+  setVercelAiGatewayApiKey,
   setZaiApiKey,
   writeOAuthCredentials,
+  VERCEL_AI_GATEWAY_DEFAULT_MODEL_REF,
   ZAI_DEFAULT_MODEL_REF,
 } from "./onboard-auth.credentials.js";
 export {