Phase 5: Lightning auto-payout with LNURL-pay and NUT-05 melt

- New lnurl_pay.c/h: LNURL-pay protocol (GET .well-known/lnurlp + callback)
- New lightning_payout.c/h: threshold-based auto-payout with multi-recipient split
- Extended nucula_wallet bridge with nucula_wallet_melt() (NUT-05)
- Config: payout section with multi-mint, multi-recipient, fee_tolerance
- Default: enabled, TollGate@coinos.io, min_payout=128, min_balance=64
- 18 new unit tests (all passing), 134 total

1 files changed, 1 insertions, 0 deletions

diff --git a/tests/unit/stubs/nucula_wallet.h b/tests/unit/stubs/nucula_wallet.h
index 260ec35..399b3b5 100644
--- a/tests/unit/stubs/nucula_wallet.h
+++ b/tests/unit/stubs/nucula_wallet.h
@@ -12,6 +12,7 @@ uint64_t nucula_wallet_balance(void);
 int nucula_wallet_proof_count(void);
 char *nucula_wallet_proofs_json(void);
 esp_err_t nucula_wallet_swap_all(void);
+esp_err_t nucula_wallet_melt(const char *bolt11_invoice, uint64_t max_fee_sats);
 void nucula_wallet_print_status(void);
 
 #endif