Add plural rules missing in i18n
user
```ruby
{
  # Dari - this isn't an iso code. Probably should be 'prs' as per ISO 639-3.
  dr: { i18n: { plural: { keys: %i[one other], rule: ->(n) { n == 1 ? :one : :other } } } },
  # Latin America and Caribbean Spanish
  "es-419": { i18n: { plural: { keys: %i[one other], rule: ->(n) { n == 1 ? :one : :other } } } },
  # Scottish Gaelic
  gd: { i18n: { plural: { keys: %i[one two few other],
                          rule:
                            lambda do |n|
                              if [1, 11].include?(n)
                                :one
                              elsif [2, 12].include?(n)
                                :two
                              elsif [3, 4, 5, 6, 7, 8, 9, 10, 13, 14, 15, 16, 17, 18, 19].include?(n)
                                :few
                              else
                                :other
                              end
                            end } } },
  # Armenian
  hy: { i18n: { plural: { keys: %i[one other], rule: ->(n) { n == 1 ? :one : :other } } } },
  # Kazakh
  kk: { i18n: { plural: { keys: %i[one other], rule: ->(n) { n == 1 ? :one : :other } } } },
  # Punjabi Shahmukhi
  "pa-pk": { i18n: { plural: { keys: %i[one other], rule: ->(n) { n == 1 ? :one : :other } } } },
  # Sinhalese
  si: { i18n: { plural: { keys: %i[one other], rule: ->(n) { n == 1 ? :one : :other } } } },
  # Uzbek
  uz: { i18n: { plural: { keys: %i[one other], rule: ->(n) { n == 1 ? :one : :other } } } },
  # Chinese Hong Kong
  "zh-hk" => { i18n: { plural: { keys: %i[one other], rule: ->(n) { n == 1 ? :one : :other } } } },
  # Chinese Taiwan
  "zh-tw" => { i18n: { plural: { keys: %i[one other], rule: ->(n) { n == 1 ? :one : :other } } } },
}
```
assistant