Update error message, fix virtual destructor

Author: giahuy98

include/tap_protocol/cktapcard.h

@@ -23,6 +23,7 @@ class CKTapCard {
  public:
   explicit CKTapCard(std::unique_ptr<Transport> transport,
                      bool first_look = true);
+  virtual ~CKTapCard() = default;
 
   friend std::unique_ptr<Tapsigner> ToTapsigner(CKTapCard&& cktapcard);
   friend std::unique_ptr<Satscard> ToSatscard(CKTapCard&& cktapcard);

src/tapsigner.cpp

@@ -171,7 +171,7 @@ Tapsigner::ChangeResponse Tapsigner::Change(const std::string& new_cvc,
                                             const std::string& cvc) {
   if (new_cvc.size() < 6 || new_cvc.size() > 32) {
     throw TapProtoException(TapProtoException::INVALID_CVC_LENGTH,
-                            "Invalid cvc length");
+                            "PIN must be between 6 and 32 digits.");
   }
   const auto [_, resp] = SendAuth(
       {

src/utils.cpp

@@ -40,7 +40,7 @@ XCVC CalcXCVC(const Bytes &cmd, const nlohmann::json::binary_t &card_nonce,
               const nlohmann::json::binary_t &his_pubkey, const Bytes &cvc) {
   if (cvc.size() < 6 || cvc.size() > 32) {
     throw TapProtoException(TapProtoException::INVALID_CVC_LENGTH,
-                            "Invalid cvc length");
+                            "PIN must be between 6 and 32 digits.");
   }
 
   const auto [my_privkey, my_pubkey] = CT_pick_keypair();