Revived Fonts Viewer as an External app (in Utilities menu) (#1484)

* Add files via upload
* Moved Font Viewer to external app

firmware/application/external/font_viewer/ui_font_viewer.hpp

@@ -0,0 +1,51 @@
+/*
+ * Copyright (C) 2023 Mark Thompson
+ *
+ * This file is part of PortaPack.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifndef __UI_DEBUG_H__
+#define __UI_DEBUG_H__
+
+#include "ui.hpp"
+#include "ui_widget.hpp"
+#include "ui_painter.hpp"
+#include "ui_menu.hpp"
+#include "ui_navigation.hpp"
+
+#include <functional>
+#include <utility>
+
+using namespace ui;
+
+namespace ui::external_app::font_viewer {
+
+class DebugFontsView : public View {
+   public:
+    DebugFontsView(NavigationView& nav);
+    void paint(Painter& painter) override;
+    std::string title() const override { return "Fonts"; };
+
+   private:
+    uint16_t display_font(Painter& painter, uint16_t y_offset, const Style* font_style, std::string_view font_name);
+    NavigationView& nav_;
+};
+
+} /* namespace ui::external_app::font_viewer */
+
+#endif /*__UI_FONT_VIEWER_H__*/