USDPT on Solana and expanded transaction APIs

New on-chain asset support and expanded APIs for withdrawals, transactions, and fees.

New currencies

• USDPT on Solana: Enabled deposits, purchases, and withdrawals in production

Transaction APIs

• Added POST /transactions/withdraw for on-chain withdrawals, including travel-rule originator and beneficiary details
• Added optional CustomerID filtering to GET /transactions
• Transaction webhooks now include the destination wallet address when available

Pricing

• Channel responses now include fixed, minimum, and percentage fee configuration
• Hosted pay-ins now support per-transaction business fees