util: add TransactionError includes and namespace declarations

Add TransactionError to node namespace and include it directly instead of
relying on indirect include through common/messages.h

This is a followup to a previous commit which moved the TransactionError enum.
These changes were done in a separate followup just to keep the previous commit
more minimal and easy to review.

src/qt/sendcoinsdialog.cpp

@@ -20,6 +20,7 @@
 #include <interfaces/node.h>
 #include <key_io.h>
 #include <node/interface_ui.h>
+#include <node/types.h>
 #include <policy/fees.h>
 #include <txmempool.h>
 #include <validation.h>