[PowerRename]Save data from the last run outside of the settings file (#28861)

* [PowerRename] Sync settings before saving last window size

* address review comments

src/common/utils/json.h

@@ -70,4 +70,40 @@ namespace json
     {
         return value; // identity function overload for convenience
     }
+
+    template<typename T, typename D = std::optional<T>>
+        requires std::constructible_from<std::optional<T>, D>
+    void get(const json::JsonObject& o, const wchar_t* name, T& destination, D default_value = std::nullopt)
+    {
+        try
+        {
+            if constexpr (std::is_same_v<T, bool>)
+            {
+                destination = o.GetNamedBoolean(name);
+            }
+            else if constexpr (std::is_arithmetic_v<T>)
+            {
+                destination = static_cast<T>(o.GetNamedNumber(name));
+            }
+            else if constexpr (std::is_same_v<T, std::wstring>)
+            {
+                destination = o.GetNamedString(name);
+            }
+            else if constexpr (std::is_same_v<T, json::JsonObject>)
+            {
+                destination = o.GetNamedObject(name);
+            }
+            else
+            {
+                static_assert(std::bool_constant<std::is_same_v<T, T&>>::value, "Unsupported type");
+            }
+        }
+        catch (...)
+        {
+            std::optional<T> maybe_default{ std::move(default_value) };
+            if (maybe_default.has_value())
+                destination = std::move(*maybe_default);
+        }
+    }
+
 }