Triple-colon ligature in ss07 has odd cursor placement in specific scenarios

In `vscode`, the interaction between the triple-colon ligature from ss07 (`:::`) and red squigglies seems to cause issues with cursor placement. Under certain circumstances, the triple-colon ligature renders correctly, but the cursor treats it as two 1.5-wide colon characters and a single 0-width colon.

**I've observed this issue in v1.100 and v1.101, but not in v1.000.**

In this screenshot, the cursor is logically placed between the 1st and 2nd colon from the left, but visually appears in the middle of the 2nd colon:


Moving the cursor right by 1 character places it at the end of the `:::`, and moving it right *again* doesn't visually move the cursor.

After moving it right once:


And again (no visual change):


It's also worth noting that this *only seems to happen* when red squigglies are involved on the right side of the triple-colon ligature:


This is with `ss07` disabled:


This is from v1.000, which doesn't appear to have the ligature:


Also, this seems to only happen with Monaspace's triple-colon ligature. Here's an example of how it looks with Fira Code and its ligatures enabled:


*(I had [originally posted about this](https://github.com/ryanoasis/nerd-fonts/issues/1503#issuecomment-2103966045) in the Nerd Fonts repo related to a different issue I had come across, but this appears to be Monaspace.)*

Beginne damit, die triple-colon ss07 ligature in VS Code v1.100 oder v1.101 mit einer roten Wellenlinie rechts davon zu reproduzieren, und vergleiche dann das Cursorverhalten mit deaktiviertem ss07, v1.000 und Fira Code. Erledigt ist die Aufgabe, wenn Cursorbewegung und visuelle Platzierung über die Ligatur hinweg konsistent bleiben, auch wenn Wellenlinien vorhanden sind.

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