docs: update generate doc to include --dotenv

docs/content/1.docs/3.api/5.commands/generate.md

@@ -6,11 +6,12 @@ description: Pre-renders every route of the application and stores the result in
 # `nuxi generate`
 
 ```{bash}
-npx nuxi generate [rootDir]
+npx nuxi generate [rootDir] [--dotenv]
 ```
 
 The `generate` command pre-renders every route of your application and stores the result in plain HTML files that you can deploy on any static hosting services. The command triggers the `nuxi build` command with the `prerender` argument set to `true`
 
 Option        | Default          | Description
 -------------------------|-----------------|------------------
 `rootDir` | `.` | The root directory of the application to generate
+`--dotenv` | `.` | Point to another `.env` file to load, **relative** to the root directory.

packages/nuxi/src/commands/generate.ts

@@ -4,7 +4,7 @@ import { defineNuxtCommand } from './index'
 export default defineNuxtCommand({
   meta: {
     name: 'generate',
-    usage: 'npx nuxi generate [rootDir]',
+    usage: 'npx nuxi generate [rootDir] [--dotenv]',
     description: 'Build Nuxt and prerender static routes'
   },
   async invoke (args) {