Adds a table to the README.md file to display a product catalog.
The catalog includes product codes, names, prices, links, platforms, and remarks for different items.
It also indicates the product category and site.
Assembles goods data from multiple files into a single, searchable catalog.
Prioritizes newer entries to reflect current stock and pricing, integrating categories, features, and use cases.
Includes unified transaction policies and self-pickup/delivery information.
