Shadda-Fatha breaks cursive positioning

[simoncozens]

It probably needs to be explicitly made a Mark glyph in the Glyph Info dialog.

$ shape variable_ttf/MarkaziText-VF.ttf ''ضَمَّة''
[uniFE94=5+802|shaddaFathaar=2+575|uniFEE4=2+1051|uni064E=0@477,376+0|uniFEBF=0+1390]

[BornaIz]

Fixed!