Added a supply check to confirm a SPL Token is actually a Metaplex NFT (#21145)

Co-authored-by: Will Roeder <roederw@titan.lan>

explorer/src/components/account/TokenAccountSection.tsx

@@ -54,7 +54,7 @@ export function TokenAccountSection({
       case "mint": {
         const info = create(tokenAccount.info, MintAccountInfo);
 
-        if (isMetaplexNFT(account.details?.data, info.decimals)) {
+        if (isMetaplexNFT(account.details?.data, info)) {
           return (
             <NonFungibleTokenMintAccountCard
               account={account}

explorer/src/pages/AccountDetailsPage.tsx

@@ -166,7 +166,7 @@ export function AccountHeader({
   const data = account?.details?.data;
   const isToken = data?.program === "spl-token" && data?.parsed.type === "mint";
 
-  if (isMetaplexNFT(data, mintInfo?.decimals)) {
+  if (isMetaplexNFT(data, mintInfo)) {
     return (
       <NFTHeader
         nftData={(data as TokenProgramData).nftData!}

explorer/src/providers/accounts/utils/isMetaplexNFT.ts

@@ -1,10 +1,15 @@
+import { MintAccountInfo } from "validators/accounts/token";
 import { ProgramData } from "..";
 
-export default function isMetaplexNFT(data?: ProgramData, decimals?: number) {
+export default function isMetaplexNFT(
+  data?: ProgramData,
+  mintInfo?: MintAccountInfo
+) {
   return (
     data?.program === "spl-token" &&
     data?.parsed.type === "mint" &&
     data?.nftData &&
-    decimals === 0
+    mintInfo?.decimals === 0 &&
+    parseInt(mintInfo.supply) === 1
   );
 }