Mint HTTP failures (swap/melt/mint-quote) were surfacing raw JSON bodies
like {"detail":"proofs already spent","code":11001} straight to the
user. Add a translator for the NUT-02/03/04/05 transaction-validation
error codes (10001-11017, 12001-12003; see
https://github.com/cashubtc/nuts/blob/main/error_codes.md) and layer it
onto the mint_client bail sites via anyhow context, so the top-level
message is actionable while the raw status/body stays available via
{:#} for logs. receive_token now surfaces the real reason (e.g. "This
ecash has already been redeemed") instead of a generic "Failed to
receive any proofs from token" when every mint in a token fails.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>