🌐 [i18n-KO] Translated perplexity.mdx to Korean

[HanNayeoniee]

What does this PR do?

Translated perplexity.mdx file of the documentation to Korean.
Added draft of model_summary.mdx file because it's referenced.
Thank you in advance for your review.

Part of #20179

Before reviewing

• Check for missing / redundant translations (번역 누락/중복 검사)
• Grammar Check (맞춤법 검사)
• Review or Add new terms to glossary (용어 확인 및 추가)
• Check Inline TOC (e.g. [[lowercased-header]])
• Check live-preview for gotchas (live-preview로 정상작동 확인)

Who can review? (Initial)

Team PseudoLab, may you please review this PR? @0525hhgus, @kihoon71, @sim-so, @gabrielwithappy, @HanNayeoniee, @wonhyeongseo, @jungnerd

Before submitting

• This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
• Did you read the contributor guideline,
  Pull Request section?
• Was this discussed/approved via a Github issue or the forum? Please add a link
  to it if that's the case.
• Did you make sure to update the documentation with your changes? Here are the
  documentation guidelines, and
  here are tips on formatting docstrings.
• Did you write any new necessary tests?

Who can review? (Final)

@sgugger, @ArthurZucker, @eunseojo May you please review this PR?

[HuggingFaceDocBuilderDev]

The documentation is not available anymore as the PR was closed or merged.

[0525hhgus]

좋은 번역 감사합니다 👍 참고한 문서까지 꼼꼼하게 추가해주셨네요!
아래 리뷰 코멘트 남깁니다 😄

[sim-so]

좋은 번역 감사합니다! 앞서 올려주신 수정 제안 이외에 추가 의견 없습니다!

[ArthurZucker]

Sorry for the late review!
Nice addition 😉

[HanNayeoniee]

@sgugger, @ArthurZucker, @eunseojo May you please review this PR?

[ArthurZucker]

Thanks a lot for updating 🤗