fix(sdk-coin-sol): handle zero decimalPlaces in token transfer builders

Solana SPL tokens with 0 decimal places (e.g. NFTs) fail during
pending approval because decimalPlaces is checked with a truthy
comparison. In JavaScript, 0 is falsy, so the condition
`data.params.decimalPlaces` evaluates to false even when
decimalPlaces is explicitly set to 0. This causes the code to skip
the sendParams/data.params branch, fall through to the token
registry lookup (which fails for unsupported tokens), and throw
"Could not determine token information" or "Invalid token name".

Use `!= null` instead of truthy checks to correctly handle 0 as a
valid value while rejecting both null and undefined. This is one of
the standard cases where loose equality is preferred over strict.

Changed in three locations:
- tokenTransferBuilder.ts buildImplementation()
- transferBuilderV2.ts buildImplementation()
- solInstructionFactory.ts tokenTransferInstruction()

TICKET: CECHO-606

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

Author: ArunBala-Bitgo

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

@@ -196,7 +196,8 @@ function tokenTransferInstruction(data: TokenTransfer): TransactionInstruction[]
   let tokenAddress: string;
   let programId: string | undefined;
   let decimalPlaces: number;
-  if (data.params.tokenAddress && data.params.decimalPlaces) {
+  // eslint-disable-next-line eqeqeq
+  if (data.params.tokenAddress && data.params.decimalPlaces != null) {
     tokenAddress = data.params.tokenAddress;
     decimalPlaces = data.params.decimalPlaces;
     programId = data.params.programId;