[Streams] Save/Remove/Check custom messages for each streamer.

[SharkyIsAKing]

Type

• BugFix
• Enhancement
• New feature

Description of the changes

This is originally from @KianBral & @willkang-1, since the last PR has been idle for so long I decided to bring this back and work on it. This will close #4668, resolving #3824 and fixes #4984

This PR has not been tested, I have merged the previous authors' commits and work, while also slowly going through #4668 comments to handle the requested changes.

Have the changes in this PR been tested?

No

[Flame442]

Unless I am misreading the diff at a glance, it looks like your commands (check/streamer/remove) are duplicated. I have a minor nitpick with the function names not being in group_sub format, but it looks like the cog already wasn't following that standard so I don't know if it's worth worrying about.

For UX consideration - do we want there to be 3 commands for setting/checking/removing, or do we want to merge check into streamer as the behavior when no argument is passed? (Or remove, I think there is precedent in other parts of the bot for either)

Additionally, you are currently failing the style checks. Please format your PR with black -l 99 using the instructions in our CONTRIBUTING.MD file.

[SharkyIsAKing]

Honestly I prefer group standards as well, the only things I've done so far are transfer the commits to keep the authors, make sure the .formats suppose i18n and adjust one of the things mentioned in the previous PR.

The rest I've not touched, personally I'd agree with merging and having them as a group_sub.