Stellar Path Payment integration for stealth payments

[truthixify]

Tier: M (2-4 days) Type: feature

Context

Stellar Path Payments let a sender pay in one asset and a receiver receive in another via on-the-fly conversion through orderbook/AMM. Wire this into the stealth send flow.

Scope

• buildPathStealthPayment({ sendAsset, receiveAsset, recipientMeta, sendMax, destAmount })
• Wraps Stellar pathPaymentStrictReceive
• Includes path-finding via Horizon /paths/strict-receive endpoint
• Emits stealth announcement post-conversion
• Slippage protection

Acceptance criteria

• Helper + tests
• Path-finding integration tested
• Documentation
• Demo follow-up for path-payment UI option

Files to start with

• New: sdk/src/chains/stellar/path-payment.ts