copy-assets update for RN Web (#84)

* copy-assets update for RN Web

* Output example

Author: benitav

client-sdk-references/react-native-and-expo/react-native-web-support.mdx

@@ -30,10 +30,11 @@ For React Native for Web, workers need to be configured when instantiating `Powe
 
 To do this, copy the contents of `node_modules/@powersync/web/dist` to the root of your project (typically in the `public `directory). To make it easier to manage these files in the `public` directory, it is recommended to place the contents in a nested directory like `@powersync`.
 
-You can run the following bash command to automate the copying process. It will create copy the contents to `/public/@powersync`.
+The [`@powersync/web`](https://github.com/powersync-ja/powersync-js/tree/main/packages/web) package includes a CLI utility which can copy the required assets to the `public` directory (configurable with the `--output` option).
 
 ```bash
-mkdir -p public/@powersync && cp -r node_modules/@powersync/web/dist/* public/@powersync/
+npx powersync-web copy-assets # Places assets into public/@powersync by default. Override with `--output path/from_current_working_dir`.
+# or pnpm powersync-web copy-assets
 ```
 
 ### 3\. Instantiate Web Workers