Disable/Pick locales in layered project

[warflash]

Describe the feature

In a similar vein as #3045, it'd be nice to be able to pick/whitelist certain locales in layers.
Currently baseLayer may have en, de, fr as locales, then any layer extending that base layer is also forced to inherit those.
For us this causes quite the headache as some projects that build on top of base layer components might only be available in certain locales, a subset of all locales in baseLayer basically.

A proposal might be a specific "(picked)(Layer)Locales" array where the language codes of the target languages can be specified.

If this needs a reproduction or example then I'm very happy to add one, thanks! 💚

Additional information

• Would you be willing to help implement this feature?
• Could this feature be implemented as a module?

Final checks

• Read the contribution guide (The contribution guideline of nuxt-modules/i18n is compliant with Nuxt too).
• Check existing discussions and issues.

[Aurion72]

I need this one too :)

[Xenossolitarius]

hmmm this already exists but it's not documented, in your child layer, @BobbieGoede probably forgot this exists bcs it's not documented. I am relying on this too and I added PR to SEO sitemap module so it supports it

  i18n: {
    defaultLocale: 'hr',
    bundle: {
      onlyLocales: ['hr', 'en'],
    },
  },