[codex] Add Korean policy pages

[jjoonleo]

Summary

• Make the public account deletion and privacy policy pages Korean by default.
• Preserve English versions at /account-deletion/en and /privacy-policy/en.
• Allow the new localized public routes through security/JWT checks and cover them in controller tests.
• Rename two Google OAuth log messages so they satisfy the existing sensitive logging policy.

Impact

Users and Play Console visitors now see Korean content at the existing public policy URLs, while English content remains available through explicit /en links.

Validation

• ./gradlew test