i18n(ko): add missing translations(Jul 8)

[yuseok89]

Fills in the missing Korean (ko) translations so the locale is back in sync with en.

• Dags list run state counts (dags.json) — added now that Show per-Dag run state counts on the Dags list page #67242, the feature that introduced these strings, has merged.
• Preset filters (common.json) and variable import (admin.json) — the remaining ko gaps.

preset appears in the ko locale for the first time here. Following the locale's existing convention, it is kept as a transliteration (프리셋) rather than translated to a native phrase — the same way other UI terms are handled (trigger → 트리거, pool → 풀, connection → 커넥션, filter → 필터).

@choo121600 @onestn @noeunkim

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[choo121600]

Could you help finish the remaining translations?

[parkhojeong]

Thanks for working on this! I’ve completed the all missing Korean translation(#69584), so would it be okay to handle these changes together in this PR?

[yuseok89]

@choo121600
Thanks for the suggestion!
I've gone ahead and filled in the remaining missing Korean translations.

@parkhojeong
Thanks, and nice work on the translations! I'm happy either way as to which PR carries this, but when I checked #69584 it looked like CI was red, so to keep things moving I went ahead and added the remaining Korean translations here. Feel free to take a look.

[choo121600]

Thank you both!

Since the static checks are currently failing on PR #69584 , we'll move forward with this completed PR. Thank you both for your work!