improving logical flow of transactions & onboarding

src/main/java/zw/qantra/tm/domain/services/TransactionService.java

@@ -29,6 +29,13 @@ public class TransactionService {
     private final TransactionRepository transactionRepository;
     private final AdditionalDataService additionalDataService;
 
+    public void reassignTransactions(String oldUid, String newUid){
+        List<Transaction> transactions = transactionRepository.findAllByUserId(oldUid);
+        transactions.forEach(transaction -> {
+            transaction.setUserId(newUid);
+            transactionRepository.save(transaction);
+        });
+    }
 
     public Transaction findById(UUID id) {
         Transaction transaction = transactionRepository.findById(id).orElseThrow(() -> new ApiException("Transaction not found for ID: " + id));