fix vitest excluding playwright e2e tests

Add e2e folder to vitest exclude patterns to prevent Vitest from
attempting to run Playwright test files. Remove duplicate vitest
config in apps/next.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: natew

apps/next/vitest.config.mts

@@ -2,6 +2,12 @@ import { defineConfig } from 'vitest/config'
 
 export default defineConfig({
   test: {
+    exclude: [
+      '**/node_modules/**',
+      '**/dist/**',
+      '**/e2e/**',
+      '**/.next/**',
+    ],
     poolOptions: {
       threads: {
         singleThread: true,