Architecture: Custom Product Type - Registers a new "Membership" product extending WooCommerce's abstract class, ensuring compatibility.
Checkout Integration: Conditional Fields - Displays membership-specific fields only when relevant products are in cart, with validation and custom table storage.
Content Restriction: Dual Methods - Supports both inline shortcode `[wcmp_restricted]` and full-page restriction via meta box checkbox.
Automation: Cron-based Expiration - Daily scheduled task expires memberships and sends notification emails automatically.