Initial implementation of WooCommerce Composable Products plugin

Implemented custom WooCommerce product type allowing customers to build their own
product bundles by selecting from predefined sets of products.

Features:
- Custom "Composable Product" type with admin interface
- Product selection by category, tag, or SKU
- Configurable selection limits (global and per-product)
- Dual pricing modes: fixed price or sum of selected products
- Modern responsive frontend with Twig templates
- AJAX add-to-cart functionality
- Full internationalization support (.pot file)
- WooCommerce settings integration
- Comprehensive documentation

Technical implementation:
- PHP 8.3+ with PSR-4 autoloading
- Twig 3.0 templating engine via Composer
- Vanilla JavaScript with jQuery for frontend interactions
- WordPress and WooCommerce hooks for seamless integration
- Security: input sanitization, validation, and output escaping
- Translation-ready with text domain 'wc-composable-product'

Documentation:
- README.md: Project overview and features
- INSTALL.md: Installation and usage guide
- IMPLEMENTATION.md: Technical architecture
- CHANGELOG.md: Version history

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

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

includes/Admin/Settings.php

@@ -0,0 +1,108 @@
+<?php
+/**
+ * Admin Settings
+ *
+ * @package WC_Composable_Product
+ */
+
+namespace WC_Composable_Product\Admin;
+
+defined('ABSPATH') || exit;
+
+/**
+ * Settings class
+ */
+class Settings extends \WC_Settings_Page {
+    /**
+     * Constructor
+     */
+    public function __construct() {
+        $this->id = 'composable_products';
+        $this->label = __('Composable Products', 'wc-composable-product');
+
+        parent::__construct();
+    }
+
+    /**
+     * Get settings array
+     *
+     * @return array
+     */
+    public function get_settings() {
+        $settings = [
+            [
+                'title' => __('Composable Products Settings', 'wc-composable-product'),
+                'type' => 'title',
+                'desc' => __('Configure default settings for composable products.', 'wc-composable-product'),
+                'id' => 'wc_composable_settings',
+            ],
+            [
+                'title' => __('Default Selection Limit', 'wc-composable-product'),
+                'desc' => __('Default number of items customers can select.', 'wc-composable-product'),
+                'id' => 'wc_composable_default_limit',
+                'type' => 'number',
+                'default' => '5',
+                'custom_attributes' => [
+                    'min' => '1',
+                    'step' => '1',
+                ],
+                'desc_tip' => true,
+            ],
+            [
+                'title' => __('Default Pricing Mode', 'wc-composable-product'),
+                'desc' => __('How to calculate the price of composable products.', 'wc-composable-product'),
+                'id' => 'wc_composable_default_pricing',
+                'type' => 'select',
+                'default' => 'sum',
+                'options' => [
+                    'sum' => __('Sum of selected products', 'wc-composable-product'),
+                    'fixed' => __('Fixed price', 'wc-composable-product'),
+                ],
+                'desc_tip' => true,
+            ],
+            [
+                'title' => __('Show Product Images', 'wc-composable-product'),
+                'desc' => __('Display product images in the selection interface.', 'wc-composable-product'),
+                'id' => 'wc_composable_show_images',
+                'type' => 'checkbox',
+                'default' => 'yes',
+            ],
+            [
+                'title' => __('Show Product Prices', 'wc-composable-product'),
+                'desc' => __('Display individual product prices in the selection interface.', 'wc-composable-product'),
+                'id' => 'wc_composable_show_prices',
+                'type' => 'checkbox',
+                'default' => 'yes',
+            ],
+            [
+                'title' => __('Show Total Price', 'wc-composable-product'),
+                'desc' => __('Display the total price as customers make selections.', 'wc-composable-product'),
+                'id' => 'wc_composable_show_total',
+                'type' => 'checkbox',
+                'default' => 'yes',
+            ],
+            [
+                'type' => 'sectionend',
+                'id' => 'wc_composable_settings',
+            ],
+        ];
+
+        return apply_filters('wc_composable_settings', $settings);
+    }
+
+    /**
+     * Output the settings
+     */
+    public function output() {
+        $settings = $this->get_settings();
+        \WC_Admin_Settings::output_fields($settings);
+    }
+
+    /**
+     * Save settings
+     */
+    public function save() {
+        $settings = $this->get_settings();
+        \WC_Admin_Settings::save_fields($settings);
+    }
+}