feat: Rich text editor and email system integration

## ✅ Step 4-5: Rich Text Editor & Integration

### RichTextEditor Component (TipTap)
- ✅ Modern WYSIWYG editor for React
- ✅ Toolbar: Bold, Italic, Lists, Links, Undo/Redo
- ✅ Variable insertion with buttons
- ✅ Placeholder support
- ✅ Clean, minimal UI

### TemplateEditor Updated
- ✅ Replaced Textarea with RichTextEditor
- ✅ Variables shown as clickable buttons
- ✅ Better UX for content editing
- ✅ HTML output for email templates

### Bootstrap Integration
- ✅ EmailManager initialized on plugin load
- ✅ Hooks into WooCommerce events automatically
- ✅ Disables WC emails to prevent duplicates

### Plugin Constants
- ✅ WOONOOW_PATH for template paths
- ✅ WOONOOW_URL for assets
- ✅ WOONOOW_VERSION for versioning

### Dependencies
- ✅ @tiptap/react
- ✅ @tiptap/starter-kit
- ✅ @tiptap/extension-placeholder
- ✅ @tiptap/extension-link

---

**Status:** Core email system complete!
**Next:** Test and create content templates 🚀

woonoow.php

@@ -9,6 +9,11 @@
 
 if (!defined('ABSPATH')) exit;
 
+// Define plugin constants
+define('WOONOOW_PATH', plugin_dir_path(__FILE__));
+define('WOONOOW_URL', plugin_dir_url(__FILE__));
+define('WOONOOW_VERSION', '0.1.0');
+
 spl_autoload_register(function ($class) {
     $prefix = 'WooNooW\\';
     $base_dir = __DIR__ . '/includes/';