Make emote completion a lot smarter

[Mm2PL]

Description

I've updated emote completion to be smarter.

Changes:

• It now has vim-like smartcase. That is given pajaW and PAJAW, if you search for PA you'll only get PAJAW.
• If smartcase search fails, the fallback is suggesting more uppercase emotes. That is if you search Pa, you'll get PAJAW, then pajaW.
• If all lowercase: you will get case insensitive matching, preferring lowercase emotes
• The emote sorting order is now well-defined: count missing characters then case difference then ASCII-betically.
• Sorting with :-completion and tab-completion is now identical.

To test you will need to actually toggle it on.
Closes #4944.

[karl-police]

It works.

But there's something questionable that I don't know.

By default, the original version does this when starting the message with a :

while the smarter completion one does this:

otherwise, the feature seems to work

happy smiley gets turned into the sad one Hmmmmmmmm

[pajlada]

LGTM 👍
Merging this in as-is without really testing its behaviour to allow more people to try it out

[karl-police]

This is fixed now.

along with this

still wondering though how the original one prioritized the emotes when just typing :, it feels like that it gave a more interesting selection of emotes

[karl-police]

What's also a bit to experiment with, is

should it show Rime or rime

when one types rIme 🤷

[karl-police]

Then how much should it even change?

Comparison:

Old one:

New one:

[Mm2PL]

With my logic, as outlined in the description, it should be: {"Rime", "rime"} when you search for "rIme" because:

• it tries a case sensitive search (query has an uppercase letter)
• no results
• it tries case insensitive and since the query has an uppercase letter it prioritizes more uppercase emotes but returns all results