Stylesheets for fonts should support an font-antialiasing property

Qt stylesheets for fonts should support setting whether a font should be anti-aliased or not.

A bug in Qt 6.7 and newer applies anti-aliasing to bdf fonts, even if fontconfig considers antialiasing off for those fonts. (QTBUG-132904).  This is notable when centering off-sets those fonts from the pixel grid.

Qt in this case ignores the fontconfig setting (which is more part of the other bug), and it is currently impossible to set an anti-aliased setting for fonts in the stylesheet (this bug).  It is possible to set "NoAntialias" or "PreferAntialias" in code, but if the program gets it's stylesheet applied at runtime, it's not possible to set the NoAntialias/PreferAntialias setting in the same place as selecting the font.

The idea of setting font antialiasing has been mentioned before:

https://lists.qt-project.org/pipermail/qt-interest-old/2009-June/008552.html

Now that the new font capabilities introduced with 6.7 are present, it has become more important to be able to configure this setting along with the font selection, which for some uses is done via stylesheet.