fix: events: should use issuer rather than ctr as per reference implementation

Author: robert-zaremba

neps/nep-0393.md

@@ -475,7 +475,7 @@ type Nep393Event {
 
 /// An event emitted by the Registry when new SBT is created.
 type Mint {
-  ctr: AccountId;    // SBT Contract minting the tokens
+  issuer: AccountId;    // SBT Contract minting the tokens
   tokens: (AccountId, u64[])[];  // list of pairs (token owner, TokenId[])
 }
 
@@ -486,15 +486,15 @@ type Mint {
 /// token IDs).
 /// Must be emitted by an SBT registry.
 type Recover {
-  ctr: AccountId         // SBT Contract recovering the tokens
+  issuer: AccountId         // SBT Contract recovering the tokens
   old_owner: AccountId;  // current holder of the SBT
   new_owner: AccountId;  // destination account.
 }
 
 /// An event emitted when existing tokens are renewed.
 /// Must be emitted by an SBT registry.
 type Renew {
-  ctr: AccountId;  // SBT Contract renewing the tokens
+  issuer: AccountId;  // SBT Contract renewing the tokens
   tokens: u64[];  // list of token ids.
 }
 
@@ -503,14 +503,14 @@ type Renew {
 /// a wallet. See also `Burn` event.
 /// Must be emitted by an SBT registry.
 type Revoke {
-  ctr: AccountId;  // SBT Contract revoking the tokens
+  issuer: AccountId;  // SBT Contract revoking the tokens
   tokens: u64[];  // list of token ids.
 }
 
 /// An event emitted when existing tokens are burned and removed from the registry.
 /// Must be emitted by an SBT registry.
 type Burn {
-  ctr: AccountId;  // SBT Contract burning the tokens
+  issuer: AccountId;  // SBT Contract burning the tokens
   tokens: u64[];  // list of token ids.
 }
 
@@ -529,6 +529,13 @@ type SoulTransfer {
   to: AccountId;
 }
 
+/// An event emitted when an issuer updates token metadata reference of existing SBTs.
+/// Must be emitted by an SBT registry.
+type TokenReference {
+  issuer: AccountId;  // Issuer account
+  tokens: u64[];  // list of token ids.
+}
+
 /// An event emitted when existing token metadata references are updated.
 type TokenReference = u64[];  // list of token ids.
 ```