[Feature]: Regex filter chat messages

[archiif]

Checklist

• This is an issue for Hyperchat, not LiveTL. I will go to the LiveTL repo to report an issue for LiveTL.
• I have checked for a duplicate or similar issue. I made sure to check closed issues as well.
• I am not reporting a bug. If I am, I will use the bug report issue template.
• By submitting this issue, you agree to follow our Code of Conduct

Is your feature request related to a problem? Please describe.

Sometimes you want to filter unwanted messages in the chat based on certain conditions.
This would be useful for things like:

• Seeing only chat messages in the language that you desire
• Spam messages
• Users you don't like

And more...

Describe the solution you'd like

A regex filter system similar to Chat Filter for YouTube Live would solve this problem.

Expected behavior

The regex filter can be applied to either the username or the message itself. The filter should also be reversible, because reversing regex patterns manually can be a pain or even downright impossible.

A convenient feature that wasn't present in the extension I mentioned above is the ability to pre-filter and strip chat emote strings before passing them to the regex filter(s). With this feature, making accurate filters would be much easier, because this avoids false positives/negatives.
(In the extension I mentioned above, emote strings are mixed into the message like: a plain :emote: chat message)

Describe alternatives you've considered

I've tried using Chat Filter for YouTube Live, but it doesn't work with HyperChat.

Anything else?

I submitted a similar issue in LiveTL/LiveTL#406, but I realized that this issue is probably more appropriate here. This extension already have filters like the member-only filter, so I think it wouldn't be out-of-place to also have a regex filter.