[Enhancement] Improve death counter in pause menu

[TerraFail451]

Linked Issues

• Enhancement: change pause menu blue balls text depending on the playable character #3759

Description

This was originally just going to be a repeat of #5229 because the PR was stale, but then I had the idea to make the death counter singular when you have one death.

This PR makes it so that if the death count is at one, the death count is singular. If it's at any other value, its plural.

This PR also allows for player characters to be given unique deaths names on the pause menu that match up with their game over animations. This is done through the deathName and deathNameSingular variables in the player's .json file. I provide those files in the funkin.assets PR (FunkinCrew/funkin.assets#316).
I chose the dual variable approach because it's way easier than trying to account for words that end in "s" in the singular form (like loss --> losses) and irregular plurals (like goose --> geese, mouse --> mice, or sheep --> sheep).

btw the default deathName is Deaths and the default deathNameSingular is Death. i just gave Pico the defaults because I couldnt think of anything better and he does in fact die so it works. but if you can think of anything better its just two lines in his .json file that you have to change.

Screenshots/Videos

Boyfriend with 0 Blue Balls

Boyfriend with 1 Blue Ball

Boyfriend with 2 Blue Balls

Pico with 0 Deaths

Pico with 1 Death

Pico with 2 Deaths

[VirtuGuy]