docs: add Scopuly to x402 compatible wallets (#2817)

Author: Scopuly

docs/build/agentic-payments/x402/README.mdx

@@ -29,6 +29,7 @@ To support x402 on Stellar, a wallet must support [auth-entry signing](../../gui
 - HOT
 - Klever
 - OneKey
+- Scopuly
 
 :::note