feat(content): add July 2026 localized news from issue #103

[ymuichiro]

Summary

• Add the July 2026 Docs Blogs article from Issue static-site/content/ja/newsに新しい記事を追加してください　2026年7月のブログ（日本語訳） #103 in all five supported locales.
• Preserve the Issue-provided Japanese article body; only control markers were omitted and remote image sources were replaced with local assets.
• Add generated translations for en, ko, zh, and zh-Hant-TW.
• Add createdAt, updatedAt, publishedAt, and complete localizations metadata so the articles appear on home pages.

Locale mapping

• en: 412 (/news/412)
• ko: 413 (/ko/news/413)
• zh: 414 (/zh/news/414)
• zh-Hant-TW: 415 (/zh-hant-tw/news/415)
• ja: 416 (/ja/news/416)

Validation

• npm --prefix static-site run build passed.
• npm --prefix static-site run test passed, including link and sitemap checks.
• Generated home pages contain each new article link and the corresponding previous article link.