Add SKALE Base Sepolia to x402 Typescript

[TheGreatAxios]

Description

This adds official support to the x402 Typescript SDK to add support for SKALE Base Sepolia Testnet. This is critical as networks not added explicitly are not supported by the package today blocking our developers.

Tests

For TypeScript: Run pnpm test from the /typescript directory Proof of Success: https://app.warp.dev/block/AcHKwkqGF7WR7xGD5mbHtG

Checklist

• [x] I have formatted and linted my code
• [x] All new and existing tests pass
• [x] My commits are signed (required for merge) -- you may need to rebase if you initially pushed unsigned commits

[cb-heimdall]

✅ Heimdall Review Status

Requirement	Status	More Info
Reviews	✅ 1/1	Denominator calculation Show calculation 1 if user is bot 0 1 if user is external 0 2 if repo is sensitive 0 From .codeflow.yml 1 Additional review requirements Show calculation Max 0 0 From CODEOWNERS 0 Global minimum 0 Max 1 1 1 if commit is unverified 0 Sum 1

[vercel[bot]]

@TheGreatAxios is attempting to deploy a commit to the Coinbase Team on Vercel.

A member of the Team first needs to authorize it.

[manuelbarbas]

Yeah! We need SKALE Base Sepolia with x402!

[benskale]

SKALE Base Sepolia with x402 is a critical next step

[KBryan]

I'm really looking forward to implementing this. Thanks @TheGreatAxios