lowlevel: Add explicit default ctor for ResultStorage on VS 2019

For some reason simply making the val_or_err field a
default-constructible type wasn't enough to work around the bug.
This commit also makes the compiler check more specific, as the
bug was present until partway through the VS 17.2 release cycle.

engine/libs/lowlevel/include/argus/lowlevel/result.hpp

@@ -41,10 +41,12 @@ namespace argus {
 
     template<typename T, typename E>
     struct ResultStorage {
-        #if defined(_MSC_VER) && _MSC_VER < 1930
-        // workaround for VS 2019 and earlier which requires std::future's type
-        // parameter type to be default-constructible
+        #if defined(_MSC_VER) && (_MSVC_STL_UPDATE < 202203L)
+        // workaround for VS versions prior to 17.2 (2022) which require
+        // std::future's type parameter type to be default-constructible
         std::optional<std::variant<reference_wrapped_t<T>, reference_wrapped_t<E>>> val_or_err;
+
+        ResultStorage(void) = default;
         #else
         std::variant<reference_wrapped_t<T>, reference_wrapped_t<E>> val_or_err;
         #endif
@@ -88,8 +90,8 @@ namespace argus {
 
         [[nodiscard]] bool is_ok(void) const {
             if constexpr (!std::is_void_v<T> && !std::is_void_v<E>) {
-                #if defined _MSC_VER && _MSC_VER < 1930
-                // workaround for VS <=2019, see comment in ResultStorage
+                #if defined _MSC_VER && _MSC_VER < 1932
+                // workaround for VS <=17.2, see comment in ResultStorage
                 // definition
                 return m_storage.val_or_err.value().index() == 0;
                 #else
@@ -114,8 +116,8 @@ namespace argus {
                 crash_ll("Attempted to call unwrap() on error-typed Result");
             }
             if constexpr (!std::is_void_v<E>) {
-                #if defined(_MSC_VER) && _MSC_VER < 1930
-                // workaround for VS <=2019, see comment in ResultStorage
+                #if defined(_MSC_VER) && (_MSVC_STL_UPDATE < 202203L)
+                // workaround for VS <=17.2, see comment in ResultStorage
                 // definition
                 return std::get<0>(m_storage.val_or_err.value());
                 #else
@@ -137,8 +139,8 @@ namespace argus {
                 crash_ll("Attempted to call unwrap() on value-typed Result");
             }
             if constexpr (!std::is_void_v<T>) {
-                #if defined(_MSC_VER) && _MSC_VER < 1930
-                // workaround for VS <=2019, see comment in ResultStorage
+                #if defined(_MSC_VER) && (_MSVC_STL_UPDATE < 202203L)
+                // workaround for VS <=17.2, see comment in ResultStorage
                 // definition
                 return std::get<1>(m_storage.val_or_err.value());
                 #else
@@ -264,8 +266,9 @@ namespace argus {
         static_assert(!std::is_void_v<T>);
 
         if constexpr (!std::is_void_v<E>) {
-            #if defined(_MSC_VER) && _MSC_VER < 1930
-            // workaround for VS <=2019, see comment in ResultStorage definition
+            #if defined(_MSC_VER) && (_MSVC_STL_UPDATE < 202203L)
+            // workaround for VS <=17.2, see comment in ResultStorage
+            // definition
             return Result<T, E>(ResultStorage<T, E> { std::make_optional(
                     std::variant<reference_wrapped_t<T>, reference_wrapped_t<E>> {
                             std::in_place_index<0>, wrap_if_reference<T>(value)