[bug] [i18n] Consider number on pluralising the number of accounts on instance

[Ryuno-Ki]

Describe the bug with a clear and concise description of what the bug is. Please include screenshots of any visual issues.

When I create my first account using the CLI and visit the landing page, GoToSocial claims that there is „1 users” on that instance.

https://github.com/superseriousbusiness/gotosocial/blob/v0.13.0-rc2/web/template/index.tmpl#L22

is the line to update.

What's your GoToSocial Version?

v0.13.0-rc2

Browser version

Firefox 115.0.2

What happened?

The template does not take into account the number on pluralisation.

What you expected to happen?

„There is 1 user”.

How to reproduce it?

Create a new GoToSocial instance and add admin account via CLI.
Then visit the landing page.

Anything else we need to know?

I've translated software in the past. This is one of the gotchas to watch out for. You're not the first project who fell for it and you won't be the last.

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/PluralRules has a high level description.

https://github.com/nicksnyder/go-i18n#go-i18n---- claims to support it.