fix(sdk-coin-sol): use null check for decimalPlaces in token transfer builders

decimalPlaces of 0 (e.g. NFTs) is falsy in JS, causing
buildImplementation to skip the sendParams branch and throw
"Could not determine token information" during PA approval.

TICKET: CECHO-606

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: ArunBala-Bitgo

modules/sdk-coin-sol/src/lib/tokenTransferBuilder.ts

@@ -124,7 +124,7 @@ export class TokenTransferBuilder extends TransactionBuilder {
         let tokenName: string;
         let programId: string | undefined;
         let decimals: number | undefined;
-        if (sendParams.tokenAddress && sendParams.programId && sendParams.decimalPlaces) {
+        if (sendParams.tokenAddress && sendParams.programId && sendParams.decimalPlaces != null) {
           tokenAddress = sendParams.tokenAddress;
           tokenName = sendParams.tokenName;
           programId = sendParams.programId;

modules/sdk-coin-sol/src/lib/transferBuilderV2.ts

@@ -138,7 +138,7 @@ export class TransferBuilderV2 extends TransactionBuilder {
           let tokenName: string;
           let programId: string | undefined;
           let decimals: number | undefined;
-          if (sendParams.tokenAddress && sendParams.programId && sendParams.decimalPlaces) {
+          if (sendParams.tokenAddress && sendParams.programId && sendParams.decimalPlaces != null) {
             tokenName = sendParams.tokenName;
             tokenAddress = sendParams.tokenAddress;
             decimals = sendParams.decimalPlaces;