[build] Move CheckTransaction from lib_server to lib_consensus

CheckTransaction is a context-free function that does not require access
to the blockchain or mempool. Move it from src/consensus/tx_verify in
lib_server to a new unit src/consensus/tx_check in lib_consensus so that
it can be called by non-server libraries.

src/test/sighash_tests.cpp

@@ -2,7 +2,7 @@
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
-#include <consensus/tx_verify.h>
+#include <consensus/tx_check.h>
 #include <consensus/validation.h>
 #include <test/data/sighash.json.h>
 #include <hash.h>

src/test/transaction_tests.cpp

@@ -8,7 +8,7 @@
 
 #include <clientversion.h>
 #include <checkqueue.h>
-#include <consensus/tx_verify.h>
+#include <consensus/tx_check.h>
 #include <consensus/validation.h>
 #include <core_io.h>
 #include <key.h>