Open upstream PR on coinbase/x402 adding paywall package #35

What problem does your feature solve?

The coinbase/x402 project currently lacks a paywall middleware package. We have a working paywall implementation in @packages/paywall/ that provides Express/Connect-compatible middleware for x402 payment gating. Contributing this upstream would benefit the entire x402 ecosystem and establish Stellar as a first-class supported network in the reference implementation.

What would you like to see?

• Review coinbase/x402 contribution guidelines and code standards
• Adapt our @packages/paywall/ code to match their project structure, naming conventions, and patterns
• Ensure the paywall middleware is network-agnostic where possible, with Stellar as a concrete implementation
• Open a PR on coinbase/x402 with the paywall package, including tests and documentation following their standards
• Coordinate with the coinbase/x402 maintainers on review feedback

What alternatives are there?

• Publish paywall as a standalone npm package outside the coinbase/x402 monorepo
• Publish it from this repo and import its modules in coinbase/x402