[Feature] Support x402 payments

**Is your feature request related to a problem? Please describe.**

Currently payments on websites are triggered by embedded JavaScript asking some web3 library to call the browser wallet extension or similar to accept and sign a payment.

x402 is a new open source protocol resurrecting the HTTP 402 Payment Required for online payments

**Describe the solution you'd like**

I would like to see OneKey detect if a HTTP request fails with error code 402 on any site, and then read the payload of that request and present the user with a dialog that has the payment details, for example

> Website example.com is requesting payment to allow access to URL example.com/x/y/z
> Do you approve the requested payment of 0.01 USDC to recipient A1B2C3?
> [Approve] [Decline]

If user approves, OneKey would resubmit the same HTTP request but add `X-Payment` headers with the signed transaction as specified in https://www.coinbase.com/en-ca/developer-platform/discover/launches/x402


No files, tests, or entry points are named. Start by locating OneKey's HTTP request interception and wallet transaction-signing entry points, then study the linked x402 specification and determine how a 402 payload, approval dialog, and X-Payment resubmission should flow; done means the full interaction is designed and validated across supported platforms.

Written by the indexing model from the issue text.