feat(wallet): add P2PKH, P2SH-P2WPKH, and P2TR (Taproot/BIP86) address types

- ScriptKind.Taproot (BIP86, purpose 86', P2WPKH → witness v1 bech32m plm1p)
  derivation wired in DerivationPaths and ChainProfiles (xprv/xpub headers,
  no SLIP-132 standard for P2TR); NBitcoin ScriptPubKeyType.TaprootBIP86
- Wizard step StepScriptType inserted between passphrase and password: 4 radio
  buttons (Legacy / Wrapped SegWit / Native SegWit★ / Taproot), localized in
  6 languages; CreateOrRestore now uses SelectedScriptKind instead of hardcoded
  NativeSegwit; back navigation updated accordingly
- BIP86 golden-vector tests (Bip86TaprootTests): output key verified against
  official Bitcoin BIP86 addresses, plm1p prefix asserted

src/Core/Chain/ChainProfile.cs

@@ -29,6 +29,9 @@ public enum ScriptKind
 
     /// <summary>P2WSH (multisig native).</summary>
     NativeSegwitMultisig,
+
+    /// <summary>P2TR key-path only (Taproot, BIP86) — witness v1, bech32m.</summary>
+    Taproot,
 }
 
 /// <summary>