remove ui namespace which is not really used, move CameraData in camera_modes.h to avoid the inclusion of canva.h

src/node_dialog_browse.cpp

@@ -135,7 +135,7 @@ void NodeDialogBrowse::init_list()
     {
         auto f_name = std::get<0>(f);
         auto f_path = std::get<1>(f);
-        ui::Image thumb = ui::Canvas::I->thumbnail_read(f_path);
+        Image thumb = Canvas::I->thumbnail_read(f_path);
         if (thumb.width == 0 || thumb.height == 0)
             continue;