post https://api-wallet-sandbox.venly.io/api/signatures//confirm
Confirms a saved signature request and prepares it for execution by updating its status
from SAVED to READY.
Process flow:
- Validates the saved signature request parameters
- For transaction signatures: Calculates and populates gas fees, nonce, and other required fields
- Updates status to READY, making it available for signing
- Sets expiration time for the confirmed request