fix: rename config import to stackConfig to avoid shadowing Vercel function config

The imported 'config' from objectstack.config.ts was being shadowed by the
exported 'config' object (Vercel function configuration) at the end of the file.
This caused stackConfig.plugins to be undefined, preventing any plugins from
being registered during kernel bootstrap.

Fixes the "CRITICAL: Required service missing: data" error on Vercel deployment.

Agent-Logs-Url: https://github.com/objectstack-ai/framework/sessions/e4cad7a6-741c-4f4d-9ab8-c69516fa044e

Co-authored-by: hotlong <50353452+hotlong@users.noreply.github.com>

Author: Claude

apps/server/server/index.ts

@@ -11,7 +11,7 @@ import { ObjectKernel } from '@objectstack/runtime';
 import { createHonoApp } from '@objectstack/hono';
 import { getRequestListener } from '@hono/node-server';
 import type { Hono } from 'hono';
-import config from '../objectstack.config';
+import stackConfig from '../objectstack.config';
 
 // ---------------------------------------------------------------------------
 // Singleton state — persists across warm Vercel invocations
@@ -33,23 +33,16 @@ async function ensureKernel(): Promise<ObjectKernel> {
 
     _bootPromise = (async () => {
         console.log('[Vercel] Booting ObjectStack Kernel...');
-        console.log('[Vercel] Config type:', typeof config);
-        console.log('[Vercel] Config keys:', Object.keys(config || {}).join(', '));
-        console.log('[Vercel] Config.plugins type:', typeof config?.plugins);
-        console.log('[Vercel] Config.plugins length:', Array.isArray(config?.plugins) ? config.plugins.length : 'not an array');
 
         try {
             const kernel = new ObjectKernel();
 
             // Register all plugins from shared config
-            const plugins = config.plugins || config.default?.plugins;
-            if (!plugins || !Array.isArray(plugins) || plugins.length === 0) {
-                throw new Error(`[Vercel] No plugins found in config. Config structure may be incorrect.`);
+            if (!stackConfig.plugins || stackConfig.plugins.length === 0) {
+                throw new Error(`[Vercel] No plugins found in stackConfig`);
             }
 
-            console.log(`[Vercel] Registering ${plugins.length} plugins...`);
-            for (const plugin of plugins) {
-                console.log(`[Vercel] Registering plugin: ${plugin?.name || 'unknown'}`);
+            for (const plugin of stackConfig.plugins) {
                 await kernel.use(plugin as any);
             }