govuk_text_area count messages are untranslatable

[m-dango]

This is a 2 part issue for the character/word count text on govuk_text_area:

1. The static message looks to be only available in English:

   govuk-form-builder/lib/govuk_design_system_formbuilder/elements/text_area.rb

   Line 78 in f29041d

   "You can enter up to #{limit_quantity} #{limit_type}"

2. js-character-count is always added, which hides the static message and AFAIK is also only currently available in English:

   govuk-form-builder/lib/govuk_design_system_formbuilder/elements/text_area.rb

   Line 42 in f29041d

   build_classes(%(textarea), %(textarea--error) => has_errors?, %(js-character-count) => limit?).prefix(brand)

   (There is some progress with changing this elsewhere: Character count alphagov/govuk-design-system-backlog#67 (comment))

The error prefix was previously updated to support translations so perhaps something similar could be accomplished here?

govuk-form-builder/lib/govuk_design_system_formbuilder/elements/error_message.rb

Line 23 in f29041d

I18n.translate("helpers.error.message_prefix", default: nil) || config.default_error_message_prefix

[peteryates]

Thanks for raising this. Yeah, making that string translatable can definitely be supported. I'll hopefully be able to take a look soon, but a PR would be welcome.