refactor: remove setup feature from build exports and config

Removes the `./setup` export entry from `package.json` and the
corresponding `src/features/setup/index.js` entry point from
`tsup.config.js`, eliminating the standalone setup feature module
from the public API and build output.

package.json

@@ -123,9 +123,6 @@
     "./provider": {
       "import": "./dist/features/provider/index.js"
     },
-    "./setup": {
-      "import": "./dist/features/setup/index.js"
-    },
     "./core/modules": {
       "import": "./dist/core/modules/index.js"
     },

src/features/setup/index.js

@@ -1,6 +0,0 @@
-/**
- * Zen Setup Module
- * Utilities for setting up Zen in a Next.js project
- */
-
-export { setupZen } from './cli.js';

tsup.config.js

@@ -16,7 +16,6 @@ export default defineConfig([
       'src/core/api/index.js',
       'src/core/api/nx-route.js',
       'src/core/database/index.js',
-      'src/features/setup/index.js',
       'src/cli/database.js',
       'src/cli/setup.js',
       'src/core/email/index.js',