Update README with WooCommerce integration documentation

- Add WooCommerce Integration and REST API to key features
- Add WooCommerce 8.0+ to optional requirements
- Add comprehensive WooCommerce Integration section with:
  - Enabling instructions
  - Product sync, cart/checkout, booking creation features
  - Order-booking synchronization details
  - PDF invoice documentation
  - Settings subtabs description
  - HPOS compatibility note
  - Admin columns info
- Update FAQ to reflect WooCommerce is now implemented

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

README.md

@@ -19,9 +19,11 @@ WP BnB Management enables WordPress to act as a full management system for B&B h
 - **Auto-Updates**: Automatic update checks and installation from license server
 - **Development Mode**: License bypass for local development environments
 - **Contact Form 7 Integration**: Accept booking requests and inquiries through CF7 forms
+- **WooCommerce Integration**: Accept payments, auto-sync rooms as products, generate invoices
 - **Dashboard**: Comprehensive admin dashboard with statistics and charts
 - **Reports**: Detailed reports with CSV and PDF export
 - **Prometheus Metrics**: Expose operational metrics for monitoring with Grafana
+- **REST API**: Comprehensive API for external integrations
 
 ### Requirements
 
@@ -29,6 +31,7 @@ WP BnB Management enables WordPress to act as a full management system for B&B h
 - PHP 8.3 or higher
 - Valid license key
 - Contact Form 7 (optional, for booking forms)
+- WooCommerce 8.0+ (optional, for payments and invoicing)
 
 ## Installation
 
@@ -444,6 +447,95 @@ The dashboard includes:
 - Today's check-ins/check-outs
 - Trend indicators
 
+## WooCommerce Integration
+
+The plugin integrates with WooCommerce to enable payment processing, automatic invoicing, and seamless order management.
+
+### Enabling WooCommerce Integration
+
+1. Install and activate WooCommerce 8.0 or higher
+2. Navigate to **WP BnB → Settings → WooCommerce**
+3. Enable "Enable WooCommerce Integration"
+4. Configure product sync and invoice settings
+
+### Features
+
+**Product Synchronization:**
+
+- Rooms are automatically synced as virtual WooCommerce products
+- Products use SKU format `bnb-room-{id}` for tracking
+- Price, description, and images are kept in sync
+- Products created/updated on room save, deleted on room deletion
+- Manual "Sync All Rooms" button in settings
+
+**Cart & Checkout:**
+
+- Add room bookings to WooCommerce cart with dates and guest count
+- Real-time availability validation prevents double-booking
+- Dynamic pricing calculated from room rates and services
+- Special checkout fields for arrival time and special requests
+- Guest information pre-filled from user profile
+
+**Booking Creation:**
+
+- Bookings automatically created on successful payment
+- Guest records created from billing information
+- Booking linked to WooCommerce order for reference
+- Booking reference displayed on order confirmation
+
+**Order-Booking Synchronization:**
+
+- Order status changes sync to booking status:
+  - Order completed → Booking confirmed
+  - Order cancelled → Booking cancelled
+  - Order refunded → Booking cancelled (full refund)
+- Partial refunds recorded without cancellation
+- Bidirectional linking between orders and bookings
+
+**PDF Invoices:**
+
+- Automatic PDF invoice generation
+- Configurable invoice number prefix (default: `INV-`)
+- Sequential invoice numbering with configurable start number
+- Auto-attach to WooCommerce order emails
+- Secure storage in `wp-content/uploads/wp-bnb-invoices/`
+- Manual generation from order admin
+
+### WooCommerce Settings
+
+**General Subtab:**
+
+- Enable/disable WooCommerce integration
+- Enable automatic product sync
+- Enable auto-attach invoices to emails
+
+**Products Subtab:**
+
+- View sync status and product count
+- Manual "Sync All Rooms Now" button
+- Product category assignment
+
+**Orders Subtab:**
+
+- Order-booking status mapping
+- View linked orders and bookings
+
+**Invoices Subtab:**
+
+- Invoice number prefix
+- Starting invoice number
+- Company details for invoice header
+- PDF styling options
+
+### HPOS Compatibility
+
+The integration is fully compatible with WooCommerce High-Performance Order Storage (HPOS). Order meta is accessed using the modern `$order->get_meta()` and `$order->update_meta_data()` methods.
+
+### Admin Columns
+
+- **Bookings list**: "WC Order" column with link to order
+- **WooCommerce Orders list**: "Booking" column with link to booking
+
 ## REST API
 
 The plugin provides a comprehensive REST API for integration with external applications, mobile apps, and third-party services.
@@ -668,7 +760,7 @@ Yes, guest data can be exported and deleted on request, and consent is tracked a
 
 ### Does it integrate with WooCommerce?
 
-WooCommerce integration for payments is planned for a future release.
+Yes! WooCommerce integration is available for payment processing and invoicing. Rooms are synced as virtual products, bookings are created on successful payment, and PDF invoices are auto-generated and attached to order emails. Navigate to **WP BnB → Settings → WooCommerce** to enable and configure the integration.
 
 ### How is guest data secured?