Implement static Notices::add() method with hybrid storage system

- Add static storage property for notices added via static method
- Maintain add() method as static while preserving instance rendering
- Merge static notices into instance notices during construction
- Update README with proper initialization and usage examples
- Reorganize documentation for better developer workflow

This enables calling Notices::add() statically while maintaining
WordPress admin notice rendering through instance-based approach.

Fixes #23

Author: alhoseany

readme.md

@@ -111,21 +111,42 @@ if ( file_exists( __DIR__ . '/vendor/easy-digital-downloads/edd-sl-sdk/edd-sl-sd
 
 ## Admin Notices
 
-The SDK includes a `Notices` class for displaying admin notices. To use it, create an instance and add notices:
+The SDK includes a `Notices` class for displaying admin notices.
+
+### Initialization
+
+First, initialize the notices system in your plugin (typically during `admin_init`):
 
 ```php
 use EasyDigitalDownloads\Updater\Admin\Notices;
 
-// Create notices instance
-$notices = new Notices();
+// Initialize notices rendering (typically in your plugin's main file or during admin_init)
+add_action( 'admin_init', function() {
+    new Notices();
+} );
+```
+
+### Adding Notices
 
-// Add a notice
-$notices->add( array(
+Once initialized, you can add notices statically from anywhere in your code:
+
+```php
+// Add a notice (static method)
+Notices::add( array(
     'id'      => 'my-notice-id',
     'type'    => 'success', // 'success', 'error', 'warning', 'info'
     'message' => 'Your license has been activated successfully!',
     'classes' => array( 'my-custom-class' ) // Optional additional CSS classes
 ) );
+
+// Example: Add notice from an action
+add_action( 'some_action', function() {
+    Notices::add( array(
+        'id'      => 'license-activated',
+        'type'    => 'success',
+        'message' => 'License activated successfully!',
+    ) );
+} );
 ```
 
-The notice will be automatically displayed on admin pages. The `Notices` class handles rendering and styling according to WordPress admin notice standards.
+The notices will be automatically displayed on admin pages. The `Notices` class handles rendering and styling according to WordPress admin notice standards.

src/Admin/Notices.php

@@ -25,11 +25,20 @@ class Notices {
 	 */
 	private $notices = array();
 
+	/**
+	 * Static notices storage.
+	 *
+	 * @var array
+	 */
+	private static $static_notices = array();
+
 	/**
 	 * Notices constructor.
 	 */
 	public function __construct() {
 		add_action( 'admin_notices', array( $this, 'render' ), 100 );
+		// Merge static notices into instance notices for rendering
+		$this->notices = array_merge( $this->notices, self::$static_notices );
 	}
 
 	/**
@@ -38,7 +47,7 @@ public function __construct() {
 	 * @since <next-version>
 	 * @param array $args The notice arguments.
 	 */
-	public function add( array $args ) {
+	public static function add( array $args ) {
 		$args = wp_parse_args(
 			$args,
 			array(
@@ -62,7 +71,7 @@ public function add( array $args ) {
 			$classes = array_merge( $classes, $args['classes'] );
 		}
 
-		$this->notices[ $args['id'] ] = array(
+		self::$static_notices[ $args['id'] ] = array(
 			'message' => $args['message'],
 			'classes' => $classes,
 		);