Multiple diacritics render on _next_ character in Windows Terminal

[Jaykul]

The first screenshot here is Cascadia Code and the second is Monaspace Neon, in the preview release of Windows Terminal.

I'm using the same diacritic three times just for the demo, because if I use two or more different diacritic marks, they all get rendered on top of each other (and in the wrong space), and it's just a mess.

1. The diacritics should be on the a, not on the b (and if I only have one, it woks, but 2 or more go on the next character)
2. If there's more than one diacritic, I expect them to stack, not overlap.

Of course, this might be a Windows Terminal bug ... but it's working OK with Cascadia Code in the same app.

Here's another example, using both accent marks. Again, Consolas first:

[kenmcd]

In Cascadia Code there are anchors on the bottom, and on the top, of the ~ diacritics - so they can stack, because they have anchors to attach to.
In Monaspace Neon it appears there are no anchors on the ~ diacritics at all.
So the second diacritic has no way to attach to the top of the previous one and just ends up floating.

Only looked at tildecomb and tildecomb.case, but I assume it is the same with the other diacritics.

Actually the shaper probably converts the a plus the first tildecomb into atilde (ã) and then tries to stack the other two on top of that. ã̃̃

In Monaspace the atilde ã also does not have a Top anchor.
So it also needs a Top anchor (and many other characters do too).
And Monaspace also needs to add the anchors to the diacritics.