feat(i18n): add command to publish localization templates

[guoyunhe]

🔗 Linked issue

❓ Type of change

• 🐞 Bug fix (a non-breaking change that fixes an issue)
• 👌 Enhancement (improving an existing functionality like performance)
• ✨ New feature (a non-breaking change that adds functionality)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

#5035

Inspired by Laravel's php artisan lang:publish command. Eject translation template of built-in validation messages to /resources/lang/en/validator.json.

Not sure if this command should be included in core or i18n.

📝 Checklist

• I have linked an issue or discussion.
• I have updated the documentation accordingly.

[thetutlage]

Hello. Thanks for creating the PR. Let's add a couple of tests for this too.

Also, we should not overwrite the existing validator.json file, until the --merge CLI flag is provided. So, by default the command is safe to run, but if there is an existing file it requires explicit opt-in

[thetutlage]

Thanks for the PR. However, we will need proper tests!

[guoyunhe]

@thetutlage updated --merge option, exit code, and tests (by Copilot)

[thetutlage]

Looks good. Let's get it in. In future, I might open up possibilities for multiple packages to register their default translations and allow this command to publish them in one-go. But, doesn't need to happen today