docs(start): clarify running builds locally

docs/framework/react/start/getting-started.md

@@ -86,6 +86,20 @@ import { defineConfig } from '@tanstack/start/config'
 export default defineConfig({})
 ```
 
+> [!NOTE]  
+> Vercel is set as the default deployment platform. To run builds locally, switch the deployment configuration to your local runtime."
+
+> ```typescript
+> // app.config.ts
+> import { defineConfig } from '@tanstack/start/config'
+>
+> export default defineConfig({
+>   deployment: {
+>     preset: 'node-server',
+>   },
+> })
+> ```
+
 ## Add the Basic Templating
 
 There are four required files for TanStack Start usage:
@@ -100,12 +114,12 @@ Once configuration is done, we'll have a file tree that looks like the following
 ```
 .
 ├── app/
-│   ├── routes/
-│   │   └── `__root.tsx`
-│   ├── `client.tsx`
-│   ├── `router.tsx`
-│   ├── `routeTree.gen.ts`
-│   └── `ssr.tsx`
+│ ├── routes/
+│ │ └── `__root.tsx`
+│ ├── `client.tsx`
+│ ├── `router.tsx`
+│ ├── `routeTree.gen.ts`
+│ └── `ssr.tsx`
 ├── `.gitignore`
 ├── `app.config.ts`
 ├── `package.json`