Shrink Big Sky beta label and make use of partial translations

[p-jackson]

Fixes #99146

Proposed Changes

Adjusts size of the BETA label to match mockups

Also attempts to make use of some existing translations if they exist.
You can see that "Create with AI" and "Create with AI {{small}}(BETA){{/small}}" are already in the process of being translated.
https://translate.wordpress.com/projects/wpcom/es/default?filters%5Bterm%5D=Create+with+AI

Why are these changes being made?

Testing Instructions

• calypso.localhost:3000/setup/onboarding and choose Big Sky compatible goals.

Pre-merge Checklist

• Has the general commit checklist been followed? (PCYsg-hS-p2)
• Have you written new tests for your changes?
• Have you tested the feature in Simple (P9HQHe-k8-p2), Atomic (P9HQHe-jW-p2), and self-hosted Jetpack sites (PCYsg-g6b-p2)?
• Have you checked for TypeScript, React or other console errors?
• Have you used memoizing on expensive computations? More info in Memoizing with create-selector and Using memoizing selectors and Our Approach to Data
• Have we added the "[Status] String Freeze" label as soon as any new strings were ready for translation (p4TIVU-5Jq-p2)?
  • For UI changes, have we tested the change in various languages (for example, ES, PT, FR, or DE)? The length of text and words vary significantly between languages.
• For changes affecting Jetpack: Have we added the "[Status] Needs Privacy Updates" label if this pull request changes what data or activity we track or use (p4TIVU-aUh-p2)?

[github-actions]

Calypso Live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-131622

Jetpack Cloud live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-131622&env=jetpack

Automattic for Agencies live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-131622&env=a8c-for-agencies

[matticbot]

This PR does not affect the size of JS and CSS bundles shipped to the user's browser.

Generated by performance advisor bot at iscalypsofastyet.com.

[a8ci18n]

This Pull Request is now available for translation here: https://translate.wordpress.com/deliverables/17220596

Some locales (Hebrew, Japanese) have been temporarily machine-translated due to translator availability. All other translations are usually ready within a few days. Untranslated and machine-translated strings will be sent for translation next Monday and are expected to be completed by the following Friday.

Thank you @p-jackson for including a screenshot in the description! This is really helpful for our translators.