Implement comprehensive stock management integration (v1.1.0)

Added complete inventory tracking system for composable products:
- Stock validation during product selection and add-to-cart
- Automatic stock deduction on order completion/processing
- Automatic stock restoration on order cancellation/refund
- Stock status indicators with visual feedback (In stock, Low stock, Out of stock)
- Prevention of out-of-stock item selection
- Low stock warnings when 5 or fewer items remain
- Order notes documenting all stock changes

New files:
- includes/Stock_Manager.php: Core stock management logic

Modified files:
- includes/Cart_Handler.php: Integrated stock validation
- includes/Product_Selector.php: Added stock info to product data
- includes/Plugin.php: Added Stock_Manager to includes
- templates/product-selector.twig: Stock status display
- assets/css/frontend.css: Stock indicator styling
- languages/*.pot/*.po: 8 new translatable strings

Version bumped to 1.1.0 with updated CHANGELOG.

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

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

IMPLEMENTATION.md

@@ -12,7 +12,7 @@ This document provides a technical overview of the WooCommerce Composable Produc
 
 ### Plugin Structure
 
-```
+```txt
 wc-composable-product/
 ├── assets/                  # Frontend assets
 │   ├── css/
@@ -42,6 +42,7 @@ wc-composable-product/
 ### 1. Main Plugin Class (`Plugin.php`)
 
 **Responsibilities:**
+
 - Singleton pattern implementation
 - Twig template engine initialization
 - Hook registration
@@ -49,6 +50,7 @@ wc-composable-product/
 - Asset enqueuing
 
 **Key Methods:**
+
 - `instance()`: Get singleton instance
 - `init_twig()`: Initialize Twig with WordPress functions
 - `render_template()`: Render Twig templates
@@ -59,6 +61,7 @@ wc-composable-product/
 **Extends:** `WC_Product`
 
 **Key Features:**
+
 - Custom product type: `composable`
 - Selection limit management (per-product or global)
 - Pricing mode (fixed or sum)
@@ -67,6 +70,7 @@ wc-composable-product/
 - Price calculation
 
 **Key Methods:**
+
 - `get_selection_limit()`: Get max selectable items
 - `get_pricing_mode()`: Get pricing calculation mode
 - `get_available_products()`: Query available products
@@ -77,6 +81,7 @@ wc-composable-product/
 **Extends:** `WC_Settings_Page`
 
 **Global Settings:**
+
 - Default selection limit
 - Default pricing mode
 - Display options (images, prices, total)
@@ -86,12 +91,14 @@ wc-composable-product/
 ### 4. Product Data Tab (`Admin/Product_Data.php`)
 
 **Responsibilities:**
+
 - Add "Composable Options" tab to product edit page
 - Render selection criteria fields
 - Save product meta data
 - Dynamic field visibility based on criteria type
 
 **Saved Meta:**
+
 - `_composable_selection_limit`: Item limit
 - `_composable_pricing_mode`: Pricing calculation
 - `_composable_criteria_type`: Selection method
@@ -102,11 +109,13 @@ wc-composable-product/
 ### 5. Product Selector (`Product_Selector.php`)
 
 **Responsibilities:**
+
 - Render frontend product selection interface
 - Prepare data for Twig template
 - Apply display settings
 
 **Template Variables:**
+
 - `products`: Available products array
 - `selection_limit`: Max selections
 - `pricing_mode`: Pricing calculation
@@ -115,12 +124,14 @@ wc-composable-product/
 ### 6. Cart Handler (`Cart_Handler.php`)
 
 **Responsibilities:**
+
 - Validate product selection
 - Add selected products to cart data
 - Calculate dynamic pricing
 - Display selected products in cart
 
 **Hooks:**
+
 - `woocommerce_add_to_cart_validation`: Validate selections
 - `woocommerce_add_cart_item_data`: Store selections
 - `woocommerce_before_calculate_totals`: Update prices
@@ -131,6 +142,7 @@ wc-composable-product/
 ### Product Selector Template (`product-selector.twig`)
 
 **Features:**
+
 - Responsive grid layout
 - Checkbox-based selection
 - Product images and prices
@@ -138,6 +150,7 @@ wc-composable-product/
 - AJAX add-to-cart
 
 **Data Attributes:**
+
 - `data-product-id`: Composable product ID
 - `data-selection-limit`: Max selections
 - `data-pricing-mode`: Pricing mode
@@ -146,6 +159,7 @@ wc-composable-product/
 ### JavaScript (`frontend.js`)
 
 **Functionality:**
+
 - Selection limit enforcement
 - Visual feedback on selection
 - Real-time price updates (sum mode)
@@ -153,6 +167,7 @@ wc-composable-product/
 - Error/success messages
 
 **Key Functions:**
+
 - `handleCheckboxChange()`: Selection logic
 - `updateTotalPrice()`: Calculate total
 - `addToCart()`: AJAX add-to-cart
@@ -161,6 +176,7 @@ wc-composable-product/
 ### CSS Styling
 
 **Approach:**
+
 - Grid-based layout (responsive)
 - Card-style product items
 - Visual selection states
@@ -242,6 +258,7 @@ wc-composable-product/
 Generated template: `languages/wc-composable-product.pot`
 
 **Supported Locales (per CLAUDE.md):**
+
 - en_US (English)
 - de_DE, de_DE_informal (German - Germany)
 - de_CH, de_CH_informal (German - Switzerland)
@@ -273,11 +290,13 @@ Generated template: `languages/wc-composable-product.pot`
 ### Hooks & Filters
 
 **Available Filters:**
+
 - `wc_composable_settings`: Modify settings array
 - `woocommerce_product_class`: Custom product class
 - `product_type_selector`: Product type registration
 
 **Customization Points:**
+
 - Twig templates (override in theme)
 - CSS styling (enqueue custom styles)
 - JavaScript behavior (extend object)
@@ -304,6 +323,7 @@ if ($product->get_type() === 'composable') {
 ## Testing Checklist
 
 ### Admin Testing
+
 - [ ] Product type appears in dropdown
 - [ ] Composable Options tab displays
 - [ ] Selection criteria toggle works
@@ -312,6 +332,7 @@ if ($product->get_type() === 'composable') {
 - [ ] Global defaults apply
 
 ### Frontend Testing
+
 - [ ] Product selector renders
 - [ ] Selection limit enforced
 - [ ] Price calculation accurate (both modes)
@@ -320,6 +341,7 @@ if ($product->get_type() === 'composable') {
 - [ ] Checkout processes correctly
 
 ### Edge Cases
+
 - [ ] Empty criteria (no products)
 - [ ] Out of stock products excluded
 - [ ] Invalid product selections rejected
@@ -349,12 +371,14 @@ Potential features for future versions:
 ## Dependencies
 
 ### Runtime
+
 - PHP 8.3+
 - WordPress 6.0+
 - WooCommerce 8.0+
 - Twig 3.0 (via Composer)
 
 ### Development
+
 - Composer for dependency management
 - WP-CLI for i18n operations (optional)
 
@@ -372,6 +396,7 @@ Potential features for future versions:
 ### Release Package
 
 Must include:
+
 - All PHP files
 - `vendor/` directory
 - Assets (CSS, JS)
@@ -380,6 +405,7 @@ Must include:
 - Documentation
 
 Must exclude:
+
 - `.git/` directory
 - `composer.lock`
 - Development files
@@ -388,12 +414,14 @@ Must exclude:
 ## Support & Maintenance
 
 ### Code Standards
+
 - WordPress Coding Standards
 - WooCommerce best practices
 - PSR-4 autoloading
 - Inline documentation
 
 ### Version Control
+
 - Semantic versioning (MAJOR.MINOR.PATCH)
 - Changelog maintained
 - Annotated git tags