[Xuepoo]

Priority: P1 | Area: area:website | Labels: feat,P1,area:website | Milestone: v0.1.0 | RFC: OQ-xxx | Task: CTX-0072

Closes #168

Summary

• Expands translations.ts to provide comprehensive single-language dictionaries for en and zh-CN.
• Adds data-i18n and data-i18n-placeholder reactive bindings to:
  • Hero badges, title, lede, and action CTAs.
  • Install Deck tabs, commands, hints, checksums, and portable labels.
  • Showcase Stage reels, tab controls, indicators, window title, tags, and composer modal.
  • Universal Linux Distribution Matrix (all 12 distro descriptions, ready statuses, copy buttons, arch and direct link labels).
  • Cyber-Manga Bento cards (stage badges, titles, descriptions, action buttons).
  • Canonical Documentation Index (category headers, docs counter, all doc article links).
  • SiteHeader search box, theme toggle, and docs navigation.
  • SiteFooter taglines, links, summaries, and edge provenance metadata.
• Zero mixed-language leakage in either English or Chinese.
• Tested and verified with Puppeteer visual snapshots (45-homepage-full-zh-pure.png, 46-homepage-full-en-pure.png, 47-distro-matrix-zh-pure.png, 48-distro-matrix-en-pure.png).