i18n(ja): automated Crowdin translation import (part 12 of 13)

[minimalsm]

Summary

• Part 12 of 13 — ja translation import split from i18n: automated Crowdin translation import (ja) #17132
• 23 files

Context

Split from the original large import PR for easier review and independent merging.

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[minimalsm]

Translation Quality Review

Language: Japanese (ja)
Score: 9.5/10

Category Analysis

Category	Score	Notes
Brand Names	9/10	Most brand names correctly kept in English. Fixed: "トルネードキャッシュ" → "Tornado Cash"
Technical Terms	10/10	Technical terminology properly translated and consistent
Grammar & Syntax	10/10	Natural Japanese with proper grammar and punctuation
Markdown Syntax	10/10	All markdown formatting preserved correctly
Completeness	10/10	All content translated with no missing sections
Typos	9/10	Fixed: "自己理型" → "自己管理型", "イーサリアノード" → "イーサリアムノード"

Issues Found & Fixed

1. Brand Name Consistency (line 41 in zero-knowledge-proofs/index.md)

   • Changed: "トルネードキャッシュ" → "Tornado Cash"
   • Brand names should remain in English for consistency

2. Typo - Incomplete Kanji (line 41 in zero-knowledge-proofs/index.md)

   • Changed: "自己理型" → "自己管理型" (custodial → non-custodial)
   • Missing kanji character corrected

3. Typo - Missing Character (line 58 in learn-quizzes.json)

   • Changed: "イーサリアノード" → "イーサリアムノード" (Ethereum node)
   • Missing "ム" character added

Summary

This is a high-quality translation batch with only minor issues. The translations are:

• Natural and fluent in Japanese
• Technically accurate with proper terminology
• Well-formatted with all markdown preserved
• Consistent with existing Japanese translations

All brand names (Tornado Cash, Zcash, Monero, GitHub, Twitter, PSE, Semaphore, World ID, etc.) are correctly kept in English. Technical terms like "ゼロ知識証明" (zero-knowledge proofs), "スマートコントラクト" (smart contracts), and "ブロックチェーン" (blockchain) are properly localized.

Recommendation: ✅ Ready to merge after fixes applied.

[wackerow]

Closing as duplicate - completed in batch translation job.