creationTime field in save info

apps/openmw/mwlua/menuscripts.cpp

@@ -89,6 +89,13 @@ namespace MWLua
                 sol::table contentFiles(lua, sol::create);
                 for (size_t i = 0; i < slot.mProfile.mContentFiles.size(); ++i)
                     contentFiles[i + 1] = Misc::StringUtils::lowerCase(slot.mProfile.mContentFiles[i]);
+
+                {
+                    auto system_time = std::chrono::system_clock::now()
+                        - (std::filesystem::file_time_type::clock::now() - slot.mTimeStamp);
+                    slotInfo["creationTime"] = std::chrono::duration<double>(system_time.time_since_epoch()).count();
+                }
+
                 slotInfo["contentFiles"] = contentFiles;
                 saves[slot.mPath.filename().string()] = slotInfo;
             }

files/lua_api/openmw/menu.lua

@@ -51,6 +51,7 @@
 -- @field #string playerName
 -- @field #string playerLevel
 -- @field #number timePlayed Gameplay time for this saved game. Note: available even with [time played](../modding/settings/saves.html#timeplayed) turned off
+-- @field #number creationTime Time at which the game was saved, as a timestamp in seconds. Can be passed as the second argument to `os.data`.
 -- @field #list<#string> contentFiles
 
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