i18n(ja): AI translation update — sync with messages.pot (2026-06-16)

[mekarpeles]

Summary

Syncs the Japanese (ja) translation file with the current messages.pot and fills previously untranslated strings.

AI attribution: All new translations generated by claude-sonnet-4-6. Please review for accuracy. Format strings and HTML markup preserved verbatim. Japanese uses polite です/ます register throughout.

Changes

• Ran scripts/i18n-messages update ja to sync with current messages.pot
• Filled 21 previously untranslated plural msgid entries
• All plural entries use identical singular/plural forms (Japanese has no grammatical plural)
• Left fuzzy entries unchanged (marked for human review)
• Cleared format-string mismatch entries via fix_format_errors.py (38 cleared)

Validation

• i18n-messages validate ja — 0 errors ✓
• i18n-messages compile ja — compiled successfully ✓
• pre-commit run --files openlibrary/i18n/ja/messages.po — clean ✓

Test results

• pytest --noconftest openlibrary/i18n/test_po_files.py -k ja — 159 passed, 0 failed ✓

Reviewer guidance

Please spot-check translations for:

1. Accuracy of meaning (does the translation convey the intent?)
2. Natural phrasing (does it sound like UI text, not literal translation?)
3. Appropriate use of です/ます polite form
4. Preserved format strings %(name)s, %(count)d, etc.

Native speakers: please edit the .po file directly on this branch.

🤖 Generated by claude-sonnet-4-6

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