refactor: move isDarkMode helper function

src/core/helpers/is_dark_mode.cpp

@@ -1,35 +0,0 @@
-/*
- * iDescriptor: A free and open-source idevice management tool.
- *
- * Copyright (C) 2025 Uncore <https://github.com/uncor3>
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU Affero General Public License as published
- * by the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU Affero General Public License for more details.
- *
- * You should have received a copy of the GNU Affero General Public License
- * along with this program. If not, see <https://www.gnu.org/licenses/>.
- */
-
-#include <QGuiApplication>
-#include <QPalette>
-#include <QStyleHints>
-
-bool isDarkMode()
-{
-#if QT_VERSION >= QT_VERSION_CHECK(6, 5, 0)
-    const auto scheme = QGuiApplication::styleHints()->colorScheme();
-    return scheme == Qt::ColorScheme::Dark;
-#else
-    const QPalette defaultPalette;
-    const auto text = defaultPalette.color(QPalette::WindowText);
-    const auto window = defaultPalette.color(QPalette::Window);
-    return text.lightness() > window.lightness();
-#endif // QT_VERSION
-}