Add local development setup instructions to README

Author: PatelUtkarsh

README.md

@@ -1,6 +1,6 @@
 # Cloudinary's WordPress Plugin
 
-Cloudinary is a cloud service that offers a solution to a web application's entire image and video management pipeline. 
+Cloudinary is a cloud service that offers a solution to a web application's entire image and video management pipeline.
 With Cloudinary, all your images are automatically uploaded, normalized, optimized and backed-up in the cloud instead of being hosted on your servers.
 
 With Cloudinary, you can stop messing around with image editors. Cloudinary can manipulate and transform your images online, on-the-fly, directly from your WordPress console. Enhance your images using every possible filter and effect you can think of. All manipulations are done in the cloud using super-powerful hardware, and all resulting images are cached, optimized (smushed and more) and delivered via a lightning fast content delivery network (CDN).
@@ -12,20 +12,18 @@ The plugin is publicly available at: [https://wordpress.org/plugins/cloudinary-i
 
 This Git repository is the development repository, while there's a mirror public SVN repository of the actual released WordPress plugin version: [https://plugins.svn.wordpress.org/cloudinary-image-management-and-manipulation-in-the-cloud-cdn/](https://plugins.svn.wordpress.org/cloudinary-image-management-and-manipulation-in-the-cloud-cdn/)
 
-
 > **Deprecation Note**
-> The legacy WordPress Plugin version (v1.x) will be deprecated as of **February 1st, 2021**, after which support, updates and bug fixes for the legacy plugin will continue in limited fashion. 
+> The legacy WordPress Plugin version (v1.x) will be deprecated as of **February 1st, 2021**, after which support, updates and bug fixes for the legacy plugin will continue in limited fashion.
 > The legacy plugin will be made obsolete on **August 1st, 2021** (end-of-life date), meaning, Version 1.x of the plugin will no longer function after that date.
-> We ask that you update to our latest WordPress Plugin v2.x before the August 1st deadline. 
-
+> We ask that you update to our latest WordPress Plugin v2.x before the August 1st deadline.
 
 ## Additional resources
 
 Additional resources are available at:
 
-* [Website](https://cloudinary.com)
-* [Documentation](https://cloudinary.com/documentation)
-* [Knowledge Base](https://support.cloudinary.com/hc/en-us)
+-   [Website](https://cloudinary.com)
+-   [Documentation](https://cloudinary.com/documentation)
+-   [Knowledge Base](https://support.cloudinary.com/hc/en-us)
 
 ## Support
 
@@ -37,6 +35,74 @@ Stay tuned for updates, tips and tutorials: [Blog](https://cloudinary.com/blog),
 
 ## Development
 
+### Prerequisites
+
+-   [Node.js](https://nodejs.org/) v16+ (see `.nvmrc`)
+-   [npm](https://www.npmjs.com/) v6.9+
+-   [Composer](https://getcomposer.org/)
+-   [Docker](https://www.docker.com/) (required for the WordPress local environment via `wp-env`)
+
+### Local Development Setup
+
+1. **Clone the repository:**
+
+    ```bash
+    git clone https://github.com/cloudinary/cloudinary_wordpress.git
+    cd cloudinary_wordpress
+    ```
+
+2. **Set the correct Node version** (if using [nvm](https://github.com/nvm-sh/nvm)):
+
+    ```bash
+    nvm install
+    nvm use
+    ```
+
+3. **Install dependencies:**
+
+    ```bash
+    npm install
+    ```
+
+    This will also run `composer install` automatically via the `postinstall` script, setting up PHP dependencies and linting tools.
+
+4. **Start the local WordPress environment:**
+
+    Make sure Docker is running, then:
+
+    ```bash
+    npm run env:start
+    ```
+
+    This spins up a WordPress instance at [http://localhost:8888](http://localhost:8888) with the plugin activated and `WP_DEBUG` enabled. A loopback fix is applied automatically so REST API self-requests work inside the container.
+
+5. **Build front-end assets:**
+
+    ```bash
+    npm run build        # One-time production build
+    npm run dev          # Watch mode for development
+    ```
+
+### Useful Commands
+
+| Command                | Description                              |
+| ---------------------- | ---------------------------------------- |
+| `npm run env:start`    | Start the local WordPress environment    |
+| `npm run env:stop`     | Stop the local WordPress environment     |
+| `npm run env:destroy`  | Remove the local environment completely  |
+| `npm run env:logs`     | View container logs                      |
+| `npm run env:cli`      | Run WP-CLI commands inside the container |
+| `npm run env:clean`    | Reset the environment (removes all data) |
+| `npm run build`        | Build front-end assets for production    |
+| `npm run dev`          | Build front-end assets in watch mode     |
+| `npm run lint`         | Run all linters (PHP, JS, CSS)           |
+| `npm run lint:php`     | Run PHP CodeSniffer                      |
+| `npm run lint:php:fix` | Auto-fix PHP linting issues              |
+| `npm run lint:js`      | Run ESLint on JavaScript files           |
+| `npm run lint:js:fix`  | Auto-fix JS linting issues               |
+| `npm run lint:style`   | Run stylelint on SCSS files              |
+| `npm run i18n`         | Generate translation files               |
+
 ### Create a Plugin Release Package
 
 Run `npm run package` to create the plugin release in the `/build` directory and package it as `cloudinary-image-management-and-manipulation-in-the-cloud-cdn.zip` in the root directory.