Clearing up Oggy and the Cockroaches tags

BUR #18757 has been approved by @nonamethanks.

rename oggy_(character) -> oggy_(oggy_and_the_cockroaches)
rename ryuuko_(oggy) -> ryuko_(oggyoggy)

Well, there aren't many posts for the titular character of Oggy and the Cockroaches, but it is still somewhat confusing that his tag is currently tagged only with "(character)" qualifier when there's also another artist tagged as Oggy, which I have renamed his tag recently to add a qualifier into Oggy (oggyoggy).

So, I'd like to change the qualifiers of both Oggy (the character) and Oggy (the artist)'s OC named Ryuuko, since it is currently only has "(oggy)" qualifiers, which may be confusing with the French cartoon show. So I have no choice but to give them distinct qualifiers, the former with the full name of the show, and the latter with additional "(oc)" qualifier.

The extra OC qualifier looks a bit silly, and doesn't really disambiguate it from the cartoon, because it could just as well be interpreted as "an OC based on the cartoon". A similar format exists for Kemono Friends OCs, for example. I think it would make more sense to give them the qualifier the artist has, so it would be ryuuko_(oggyoggy).

Agree with Damian and looks like the Mugen character is named Ryuko.

Alright, changed the BUR for Mugen OC tag.

The bulk update request #18757 (forum #249284) has been approved by @nonamethanks.