Merge bitcoin/bitcoin#27117: fuzz: avoid redundant dup key checks when creating Miniscript nodes

c1b7bd0 fuzz: avoid redundant dup key checks when creating Miniscript nodes (Antoine Poinsot)

Pull request description:

  I thought i had done that already in #24149, but it must have slipped through the rebase. It's a 2x speed improvement against the existing corpora and will probably be much more as we extend them with larger nodes.

ACKs for top commit:
  sipa:
    ACK c1b7bd0

Tree-SHA512: 9e6ceb6254183964b6c5538e21ba6321df95a68acb343a15a6ecfef5c51a1980d2627df5aeef9aef1db41656e18cc4f3bc96e6f24314d12fa60368b04a350001

Author: fanquake

src/test/fuzz/miniscript.cpp

@@ -253,7 +253,9 @@ using Type = miniscript::Type;
 using miniscript::operator"" _mst;
 
 //! Construct a miniscript node as a shared_ptr.
-template<typename... Args> NodeRef MakeNodeRef(Args&&... args) { return miniscript::MakeNodeRef<CPubKey>(KEY_COMP, std::forward<Args>(args)...); }
+template<typename... Args> NodeRef MakeNodeRef(Args&&... args) {
+    return miniscript::MakeNodeRef<CPubKey>(miniscript::internal::NoDupCheck{}, std::forward<Args>(args)...);
+}
 
 /** Information about a yet to be constructed Miniscript node. */
 struct NodeInfo {
@@ -762,6 +764,7 @@ NodeRef GenNode(F ConsumeNode, Type root_type = ""_mst, bool strict_valid = fals
         }
     }
     assert(stack.size() == 1);
+    stack[0]->DuplicateKeyCheck(KEY_COMP);
     return std::move(stack[0]);
 }