Clean up things that include script/standard.h

Remove standard.h from files that don't use anything in it, and include
it in files that do.

src/wallet/wallet.cpp

@@ -26,6 +26,7 @@
 #include <script/descriptor.h>
 #include <script/script.h>
 #include <script/signingprovider.h>
+#include <script/standard.h>
 #include <support/cleanse.h>
 #include <txmempool.h>
 #include <util/bip32.h>