wallet: scaffold BIP86 addrtype

diff --git a/bitcoin/tx.c b/bitcoin/tx.c
index 4c1a63de..e03b98b3 100644
--- a/bitcoin/tx.c
+++ b/bitcoin/tx.c
@@ -940,6 +940,7 @@ size_t bitcoin_tx_input_witness_weight(enum utxotype utxotype)
 		/* In practice, these predate anchors, so: */
 		return 1 + 1 + bitcoin_tx_input_sig_weight();
 	case UTXO_P2TR:
+	case UTXO_P2TR_BIP86:
 		return 1 + 64;
 	}
 	abort();
diff --git a/bitcoin/tx.h b/bitcoin/tx.h
index 4b7134e0..4690b6fb 100644
--- a/bitcoin/tx.h
+++ b/bitcoin/tx.h
@@ -53,6 +53,8 @@ enum utxotype {
 	UTXO_P2WSH_FROM_CLOSE = 3,
 	/* "p2tr" addresses. */
 	UTXO_P2TR = 4,
+	/* "bip86" addresses (P2TR with BIP86 derivation). */
+	UTXO_P2TR_BIP86 = 5,
 };
 
 struct bitcoin_tx_output *new_tx_output(const tal_t *ctx,
diff --git a/common/utxo.c b/common/utxo.c
index ca978c50..f94c85ae 100644
--- a/common/utxo.c
+++ b/common/utxo.c
@@ -46,6 +46,8 @@ const char *utxotype_to_str(enum utxotype utxotype)
 		return "p2wsh_from_close";
 	case UTXO_P2TR:
 		return "p2tr";
+	case UTXO_P2TR_BIP86:
+		return "p2tr_bip86";
 	}
 	abort();
 }
diff --git a/wallet/test/run-wallet.c b/wallet/test/run-wallet.c
index c3d04111..d3087ccc 100644
--- a/wallet/test/run-wallet.c
+++ b/wallet/test/run-wallet.c
@@ -327,9 +327,6 @@ bool fromwire_hsmd_client_hsmfd_reply(const void *p UNNEEDED)
 /* Generated stub for fromwire_hsmd_cupdate_sig_reply */
 bool fromwire_hsmd_cupdate_sig_reply(const tal_t *ctx UNNEEDED, const void *p UNNEEDED, u8 **cu UNNEEDED)
 { fprintf(stderr, "fromwire_hsmd_cupdate_sig_reply called!\n"); abort(); }
-/* Generated stub for fromwire_hsmd_derive_bip86_key_reply */
-bool fromwire_hsmd_derive_bip86_key_reply(const void *p UNNEEDED, struct ext_key *bip86_base UNNEEDED)
-{ fprintf(stderr, "fromwire_hsmd_derive_bip86_key_reply called!\n"); abort(); }
 /* Generated stub for fromwire_hsmd_derive_secret_reply */
 bool fromwire_hsmd_derive_secret_reply(const void *p UNNEEDED, struct secret *secret UNNEEDED)
 { fprintf(stderr, "fromwire_hsmd_derive_secret_reply called!\n"); abort(); }
@@ -711,9 +708,6 @@ u8 *towire_hsmd_client_hsmfd(const tal_t *ctx UNNEEDED, const struct node_id *id
 /* Generated stub for towire_hsmd_cupdate_sig_req */
 u8 *towire_hsmd_cupdate_sig_req(const tal_t *ctx UNNEEDED, const u8 *cu UNNEEDED)
 { fprintf(stderr, "towire_hsmd_cupdate_sig_req called!\n"); abort(); }
-/* Generated stub for towire_hsmd_derive_bip86_key */
-u8 *towire_hsmd_derive_bip86_key(const tal_t *ctx UNNEEDED, u32 index UNNEEDED, bool is_change UNNEEDED)
-{ fprintf(stderr, "towire_hsmd_derive_bip86_key called!\n"); abort(); }
 /* Generated stub for towire_hsmd_derive_secret */
 u8 *towire_hsmd_derive_secret(const tal_t *ctx UNNEEDED, const u8 *info UNNEEDED)
 { fprintf(stderr, "towire_hsmd_derive_secret called!\n"); abort(); }
@@ -802,6 +796,14 @@ u8 *towire_hsmd_get_channel_basepoints(const tal_t *ctx UNNEEDED, const struct n
 {
 	return NULL;
 }
+u8 *towire_hsmd_derive_bip86_key(const tal_t *ctx UNNEEDED, u32 index UNNEEDED, bool is_change UNNEEDED)
+{
+	return NULL;
+}
+bool fromwire_hsmd_derive_bip86_key_reply(const void *p UNNEEDED, struct ext_key *bip86_base UNNEEDED)
+{
+	return true;
+}
 bool wire_sync_write(int fd UNNEEDED, const void *msg TAKES UNNEEDED)
 {
 	return true;
diff --git a/wallet/wallet.c b/wallet/wallet.c
index 50d9ac7d..3a53ba70 100644
--- a/wallet/wallet.c
+++ b/wallet/wallet.c
@@ -169,6 +169,9 @@ static void our_addresses_add_for_index(struct wallet *w, u32 i)
 				  tal_bytelen(scriptpubkey),
 				  ADDR_P2TR);
 		return;
+	case ADDR_P2TR_MNEMONIC:
+		/* BIP86 addresses not yet implemented */
+		return;
 	}
 	abort();
 }
@@ -3186,6 +3189,9 @@ static void got_utxo(struct wallet *w,
 	case ADDR_P2TR:
 		utxo->utxotype = UTXO_P2TR;
 		goto type_ok;
+	case ADDR_P2TR_MNEMONIC:
+		utxo->utxotype = UTXO_P2TR_BIP86;
+		goto type_ok;
 	case ADDR_ALL:
 		break;
 	}
diff --git a/wallet/wallet.h b/wallet/wallet.h
index 56f61b28..81bbe2c7 100644
--- a/wallet/wallet.h
+++ b/wallet/wallet.h
@@ -283,6 +283,7 @@ enum addrtype {
 	ADDR_P2SH_SEGWIT = 1,
 	ADDR_BECH32 = 2,
 	ADDR_P2TR = 4,
+	ADDR_P2TR_MNEMONIC = 8,
 	ADDR_ALL = (ADDR_BECH32 + ADDR_P2TR)
 };
 
@@ -295,6 +296,9 @@ static inline enum addrtype wallet_addrtype_in_db(enum addrtype t)
 	case ADDR_P2TR:
 		BUILD_ASSERT(ADDR_P2TR == 4);
 		return t;
+	case ADDR_P2TR_MNEMONIC:
+		BUILD_ASSERT(ADDR_P2TR_MNEMONIC == 8);
+		return t;
 	case ADDR_ALL:
 		BUILD_ASSERT(ADDR_ALL == 6);
 		return t;
diff --git a/wallet/walletrpc.c b/wallet/walletrpc.c
index a39f6851..e8fbdb1a 100644
--- a/wallet/walletrpc.c
+++ b/wallet/walletrpc.c
@@ -50,6 +50,7 @@ encode_pubkey_to_addr(const tal_t *ctx,
 		ok = segwit_addr_encode(out, hrp, 0, h160.u.u8, sizeof(h160));
 		goto done;
 
+	case ADDR_P2TR_MNEMONIC:
 	case ADDR_P2TR: {
 		u8 *p2tr_spk = scriptpubkey_p2tr(ctx, pubkey);
 		u8 *x_key = p2tr_spk + 2;