Merge bitcoin/bitcoin#29421: net: make the list of known message types a compile time constant

b3efb48673 protocol: make message types constexpr (Vasil Dimov)
2fa9de06c2 net: make the list of known message types a compile time constant (Vasil Dimov)

Pull request description:

  Turn the `std::vector` to `std::array` because it is cheaper and allows us to have the number of the messages as a compile time constant: `ALL_NET_MESSAGE_TYPES.size()` which can be used in future code to build other `std::array`s with that size.

  ---

  This change is part of https://github.com/bitcoin/bitcoin/pull/29418 but it makes sense on its own and would be good to have it, regardless of the fate of https://github.com/bitcoin/bitcoin/pull/29418. Also, if this is merged, that would reduce the size of https://github.com/bitcoin/bitcoin/pull/29418, thus the current standalone PR.

ACKs for top commit:
  achow101:
    ACK b3efb48673
  jonatack:
    ACK b3efb48673
  maflcko:
    utACK b3efb48673 🎊
  willcl-ark:
    ACK b3efb48673

Tree-SHA512: 6d3860c138c64514ebab13d97ea67893e2d346dfac30a48c3d9bc769a1970407375ea4170afdb522411ced306a14a9af4eede99e964d1fb1ea3efff5d5eb57af

test/fuzz/test_runner.py

@@ -215,12 +215,12 @@ def transform_process_message_target(targets, src_dir):
     p2p_msg_target = "process_message"
     if (p2p_msg_target, {}) in targets:
         lines = subprocess.run(
-            ["git", "grep", "--function-context", "g_all_net_message_types{", src_dir / "src" / "protocol.cpp"],
+            ["git", "grep", "--function-context", "ALL_NET_MESSAGE_TYPES{", src_dir / "src" / "protocol.h"],
             check=True,
             stdout=subprocess.PIPE,
             text=True,
         ).stdout.splitlines()
-        lines = [l.split("::", 1)[1].split(",")[0].lower() for l in lines if l.startswith("src/protocol.cpp-    NetMsgType::")]
+        lines = [l.split("::", 1)[1].split(",")[0].lower() for l in lines if l.startswith("src/protocol.h-    NetMsgType::")]
         assert len(lines)
         targets += [(p2p_msg_target, {"LIMIT_TO_MESSAGE_TYPE": m}) for m in lines]
     return targets