Merge bitcoin/bitcoin#25108: tidy: add modernize-use-default-member-init

ac6fbf2c83 tidy: use modernize-use-default-member-init (fanquake)
7aa40f5563 refactor: use C++11 default initializers (fanquake)

Pull request description:

  Refactor and then enable [`modernize-use-default-member-init`](https://clang.llvm.org/extra/clang-tidy/checks/modernize-use-default-member-init.html) in our `clang-tidy` job.

Top commit has no ACKs.

Tree-SHA512: 536b406f20639f8c588fe9e96175ec60c7bb825506b2670b562370b2f572801c24203c483443be3c199e1b958c0765d4532e57c57a4e78689162a1dd422d844f

src/wallet/context.cpp

@@ -5,6 +5,6 @@
 #include <wallet/context.h>
 
 namespace wallet {
-WalletContext::WalletContext() {}
-WalletContext::~WalletContext() {}
+WalletContext::WalletContext() = default;
+WalletContext::~WalletContext() = default;
 } // namespace wallet

src/wallet/rpc/transactions.cpp

@@ -64,9 +64,7 @@ struct tallyitem
     int nConf{std::numeric_limits<int>::max()};
     std::vector<uint256> txids;
     bool fIsWatchonly{false};
-    tallyitem()
-    {
-    }
+    tallyitem() = default;
 };
 
 static UniValue ListReceived(const CWallet& wallet, const UniValue& params, const bool by_label, const bool include_immature_coinbase) EXCLUSIVE_LOCKS_REQUIRED(wallet.cs_wallet)

src/wallet/walletdb.cpp

@@ -314,8 +314,7 @@ public:
     std::map<uint160, CHDChain> m_hd_chains;
     bool tx_corrupt{false};
 
-    CWalletScanState() {
-    }
+    CWalletScanState() = default;
 };
 
 static bool