chore: improve workflow names and fix CSS indentation consistency (#18)

* fix: resolve plugin class loading reliability issues

* fix: address CodeRabbit XSS and accessibility findings from PR #18

- admin/js/admin-scripts.js: replace HTML string interpolation in showNotice
  with DOM API construction and .text() to prevent XSS; whitelist type values
- admin/js/update-source-selector.js: replace .html(message) with .text(message)
  in showMessage to prevent XSS from AJAX response content
- admin/templates/modal.php: add role=dialog, aria-modal=true, aria-labelledby
  for screen reader semantics; replace <span> close control with <button> for
  keyboard operability and proper ARIA role

tests/phpunit/bootstrap.php

@@ -46,7 +46,7 @@ if ( getenv( 'WP_PHPUNIT__DIR' ) ) {
     // Include plugin files needed for tests.
     require_once WPST_PLUGIN_DIR . 'includes/class-core.php';
     require_once WPST_PLUGIN_DIR . 'includes/class-plugin.php';
-    if ( file_exists( WPST_PLUGIN_DIR . 'admin/lib/admin.php' ) ) {
-        require_once WPST_PLUGIN_DIR . 'admin/lib/admin.php';
+    if ( file_exists( WPST_PLUGIN_DIR . 'includes/Admin/class-admin.php' ) ) {
+        require_once WPST_PLUGIN_DIR . 'includes/Admin/class-admin.php';
     }
 }

tests/phpunit/test-admin.php

@@ -101,17 +101,12 @@ class AdminTest extends \WP_Mock\Tools\TestCase {
             'return' => 'wp_plugin_starter_template_settings',
         ]);
 
-        // Mock WordPress functions used in the method
-        WP_Mock::userFunction('plugin_dir_url', [
-            'return' => 'http://example.com/wp-content/plugins/wp-plugin-starter-template/includes/Admin/',
-        ]);
-
         // Mock wp_enqueue_style
         WP_Mock::userFunction('wp_enqueue_style', [
             'times' => 1,
             'args' => [
                 'wpst-admin-styles',
-                'http://example.com/wp-content/plugins/wp-plugin-starter-template/includes/Admin/../../admin/css/admin-styles.css',
+                'http://example.org/wp-content/plugins/wp-plugin-starter-template/admin/css/admin-styles.css',
                 [],
                 '1.0.0',
             ],
@@ -122,7 +117,7 @@ class AdminTest extends \WP_Mock\Tools\TestCase {
             'times' => 1,
             'args' => [
                 'wpst-admin-script',
-                'http://example.com/wp-content/plugins/wp-plugin-starter-template/includes/Admin/../../admin/js/admin-scripts.js',
+                'http://example.org/wp-content/plugins/wp-plugin-starter-template/admin/js/admin-scripts.js',
                 ['jquery'],
                 '1.0.0',
                 true,