Fix Settings.php class loading timing issue (v1.1.2)

CRITICAL BUG FIX: v1.1.1 still had the same error!

Root cause analysis:
- v1.1.1 changed hook to woocommerce_init but error persisted
- Real issue: Settings.php was require_once'd in Plugin::includes()
- At that point, class extends WC_Settings_Page which doesn't exist yet
- Even woocommerce_init fires before WC_Settings_Page is loaded

Solution:
- Removed require_once from Plugin::includes() (line 93)
- Moved require_once to Plugin::add_settings_page() (line 196)
- Settings.php now loads on-demand via woocommerce_get_settings_pages filter
- This filter fires when WooCommerce has loaded all settings classes

Changes:
- includes/Plugin.php: Delayed Settings.php inclusion with explanatory comment
- wc-composable-product.php: Version bump to 1.1.2
- CHANGELOG.md: Documented fix and noted v1.1.1 was insufficient

This addresses the actual root cause that persisted through 3 versions.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

includes/Plugin.php

@@ -90,7 +90,8 @@ class Plugin {
      * Include required files
      */
     private function includes() {
-        require_once WC_COMPOSABLE_PRODUCT_PATH . 'includes/Admin/Settings.php';
+        // Note: Settings.php is NOT included here because it extends WC_Settings_Page
+        // which isn't loaded until later. It's included in add_settings_page() instead.
         require_once WC_COMPOSABLE_PRODUCT_PATH . 'includes/Admin/Product_Data.php';
         require_once WC_COMPOSABLE_PRODUCT_PATH . 'includes/Product_Type.php';
         require_once WC_COMPOSABLE_PRODUCT_PATH . 'includes/Stock_Manager.php';
@@ -191,6 +192,8 @@ class Plugin {
      * @return array
      */
     public function add_settings_page($settings) {
+        // Include Settings.php here, when WC_Settings_Page is guaranteed to be loaded
+        require_once WC_COMPOSABLE_PRODUCT_PATH . 'includes/Admin/Settings.php';
         $settings[] = new Admin\Settings();
         return $settings;
     }