demo x402 agent

[GPSxtreme]

Overview

• Adds a demo x402 agent that communicates with the browser wallet example server from the x402 repo examples
• We can use the similar setup, ie hosting a paywalled api server and create tools to communicate with this api and provide those tools to the agent and create some utility out of it.
• For payment setup on the agent/server side we are using x402-axios (hono also available) package for payment middleware which makes this setup pretty easy & just with couple lines of code we can simply change which routes are paywalled and which are not with ease.