GamesSettings: Add chess settings :^)

This adds a tab for configuring the appearance of Chess, along with a
preview.

Userland/Applications/GamesSettings/ChessSettingsWidget.h

@@ -0,0 +1,39 @@
+/*
+ * Copyright (c) 2023, Sam Atkins <atkinssj@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/Array.h>
+#include <AK/StringView.h>
+#include <LibGUI/SettingsWindow.h>
+#include <LibGfx/Color.h>
+
+namespace GamesSettings {
+
+class ChessGamePreview;
+
+class ChessSettingsWidget final : public GUI::SettingsWindow::Tab {
+    C_OBJECT_ABSTRACT(ChessSettingsWidget)
+public:
+    static ErrorOr<NonnullRefPtr<ChessSettingsWidget>> try_create();
+    virtual ~ChessSettingsWidget() override = default;
+
+    virtual void apply_settings() override;
+    virtual void reset_default_values() override;
+
+private:
+    ChessSettingsWidget() = default;
+    ErrorOr<void> initialize();
+
+    Vector<DeprecatedString> m_piece_sets;
+
+    RefPtr<ChessGamePreview> m_preview;
+    RefPtr<GUI::ComboBox> m_piece_set_combobox;
+    RefPtr<GUI::ComboBox> m_board_theme_combobox;
+    RefPtr<GUI::CheckBox> m_show_coordinates_checkbox;
+};
+
+}