feat: Add spoiler, superscript and subscript attached modifiers

[VoreckLukas]

The change in 582 has been made by my autoformatter doing format on save. I didn't notice it until I made this pr

[NTBBloodbath]

Hi, thanks for the changes!

Could you please also modify the according tests for the attached modifiers? CI seems to be failing :p

[VoreckLukas]

Sorry, didn't notice the tests, I made the changes at 1 AM 😅

It will be done

[VoreckLukas]

I looked into it and found the issue. The failing test is testing this snippet

"this *is* a test",
"hello, *world*!",
"*hello, world!*",
"*hello*, world!
"*/hello/*, world!",
"*hi!* how are you?",
"this *is a test",
"this *is/ a test",
"this *is*/ a test",
"this */is/*/ a test",

Due to an attached modifier being able to span multiple paragraph segments the exclamation marks cause it to parse as a spoiler. I'm going to escape the exclamation marks and see if it fixes the test

[VoreckLukas]

Seems like it's not only that, it somehow messes up parsing of attached modifiers altogether

[benlubas]

So the issue here is with the attached modifier parsing that becomes very apparent when these common symbols are added as attached modifiers.

On main, I can replicate the issue that we see on this branch with an example like: *hello/ world_*. This should be bold, but instead it's parsed as just plain text.

I don't think this is at all easy to solve, will probably require a re-write of a lot of the detached modifier parsing code.

[benlubas]

issue is somewhat related to #9