fix(Transaction): prevent regeneration of manually set TransactionId

Author: Atharva1723

src/sdk/main/src/Transaction.cc

@@ -150,6 +150,18 @@ struct Transaction<SdkRequestType>::TransactionImpl
    * The public key of the trusted batch assembler.
    */
   std::shared_ptr<Key> mBatchKey = nullptr;
+  /**
+ * 
+ * This flag is used to determine whether a Transaction's TransactionId
+ * should be regenerated if the Transaction expires. 
+ * 
+ * - If `mTransactionIdManualSet` is true, the TransactionId was set manually by the user,
+ *   and it **must not be regenerated**, regardless of the client-wide or transaction-specific
+ *   regeneration policies.
+ * - If `mTransactionIdManualSet` is false (default), the TransactionId may be regenerated
+ *   based on the transaction's own `mTransactionIdRegenerationPolicy` or the client's policy.
+ */
+  bool mTransactionIdManualSet = false;
 };
 
 //-----
@@ -654,6 +666,7 @@ SdkRequestType& Transaction<SdkRequestType>::setTransactionId(const TransactionI
 {
   requireNotFrozen();
   mImpl->mTransactionId = id;
+  mImpl->mTransactionIdManualSet = true; 
   return static_cast<SdkRequestType&>(*this);
 }
 
@@ -1245,9 +1258,13 @@ typename Executable<SdkRequestType, proto::Transaction, proto::TransactionRespon
   }
 
   bool shouldRegenerate = DEFAULT_REGENERATE_TRANSACTION_ID;
+  if (mImpl->mTransactionIdManualSet)
+  {
+    shouldRegenerate = false;
+  }
 
   // Follow this Transaction's policy if it has been explicitly set.
-  if (mImpl->mTransactionIdRegenerationPolicy.has_value())
+  else if (mImpl->mTransactionIdRegenerationPolicy.has_value())
   {
     shouldRegenerate = mImpl->mTransactionIdRegenerationPolicy.value();
   }