wallet, refactor: Add wallet::NotifyWalletLoaded() function

This change is a prerequisite for the following bugfix.

src/wallet/wallet.cpp

@@ -167,6 +167,14 @@ std::unique_ptr<interfaces::Handler> HandleLoadWallet(WalletContext& context, Lo
     return interfaces::MakeHandler([&context, it] { LOCK(context.wallets_mutex); context.wallet_load_fns.erase(it); });
 }
 
+void NotifyWalletLoaded(WalletContext& context, const std::shared_ptr<CWallet>& wallet)
+{
+    LOCK(context.wallets_mutex);
+    for (auto& load_wallet : context.wallet_load_fns) {
+        load_wallet(interfaces::MakeWallet(context, wallet));
+    }
+}
+
 static Mutex g_loading_wallet_mutex;
 static Mutex g_wallet_release_mutex;
 static std::condition_variable g_wallet_release_cv;
@@ -2904,12 +2912,7 @@ std::shared_ptr<CWallet> CWallet::Create(WalletContext& context, const std::stri
         return nullptr;
     }
 
-    {
+    NotifyWalletLoaded(context, walletInstance);
-        LOCK(context.wallets_mutex);
-        for (auto& load_wallet : context.wallet_load_fns) {
-            load_wallet(interfaces::MakeWallet(context, walletInstance));
-        }
-    }
 
     {
         LOCK(walletInstance->cs_wallet);

src/wallet/wallet.h

@@ -67,6 +67,7 @@ std::shared_ptr<CWallet> LoadWallet(WalletContext& context, const std::string& n
 std::shared_ptr<CWallet> CreateWallet(WalletContext& context, const std::string& name, std::optional<bool> load_on_start, DatabaseOptions& options, DatabaseStatus& status, bilingual_str& error, std::vector<bilingual_str>& warnings);
 std::shared_ptr<CWallet> RestoreWallet(WalletContext& context, const fs::path& backup_file, const std::string& wallet_name, std::optional<bool> load_on_start, DatabaseStatus& status, bilingual_str& error, std::vector<bilingual_str>& warnings);
 std::unique_ptr<interfaces::Handler> HandleLoadWallet(WalletContext& context, LoadWalletFn load_wallet);
+void NotifyWalletLoaded(WalletContext& context, const std::shared_ptr<CWallet>& wallet);
 std::unique_ptr<WalletDatabase> MakeWalletDatabase(const std::string& name, const DatabaseOptions& options, DatabaseStatus& status, bilingual_str& error);
 
 //! -paytxfee default