feat: showcase i18n with structured JSON + build-time MDX generation

[xuewenjie123]

feat: Showcase i18n with structured JSON + build-time MDX generation

This PR implements a complete i18n solution for showcase pages, supporting all 7 languages (zh, en, de, fr, ja, pt-BR, ru). It adopts a structured JSON + build-time generation approach for maximum maintainability.

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Changes

🏗️ Architecture: Structured JSON Data Source

• Structured JSON format: Replaced raw body string with structured fields (overview, steps, callouts), making showcase content easy to configure without writing MDX markup
• Build-time MDX generation: generate-showcase-mdx.js reads structured JSON and generates MDX files for all 7 locales, with auto-generated section headers, meta components, media blocks, and CTA
• zh.json as source of truth: All showcases must be defined in zh.json; missing translations in other languages automatically fall back to Chinese

📝 Data Generation

• Added author and date fields to showcase data
• Updated generate-showcase-data.js with date-based primary sorting (newest first)
• Showcase index page now displays items in reverse chronological order

🌐 i18n Support for Components

• ShowcaseDetailCta: Now uses locale-aware links and translated texts for all 7 supported languages
• ShowcaseDetailMeta: Supports author prop display
• All showcase components (video-showcase-index, video-showcase-detail, showcase-detail, showcase-cards): Dynamic locale detection via useLocale() hook, replacing hardcoded /zh/ paths

🔧 Scripts

Script	Purpose
generate-showcase-mdx.js	JSON → MDX generation for all locales (runs at build time)
generate-showcase-data.js	Updated with author/date fields and reverse date sorting
extract-showcase-data.js	MDX → JSON extraction utility (for migration)
restructure-showcase-json.js	body → structured fields migration (one-time use)

📖 Documentation

• Added SHOWCASE_I18N_GUIDE.md with complete guide for adding/translating showcases

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Files Changed

• ~292 files across all 7 supported locales
• 7 JSON data files: showcase-i18n/{zh,en,de,fr,ja,pt-BR,ru}.json
• 234 generated MDX files: content/{lang}/showcase/*.mdx (39 showcases × 6 non-zh locales)
• 39 updated MDX files: content/zh/showcase/*.mdx
• 5 component files: showcase-detail-meta, video-showcase-index, video-showcase-detail, showcase-detail, showcase-cards
• 4 script files: generate-showcase-mdx, generate-showcase-data, extract-showcase-data, restructure-showcase-json
• 1 doc file: SHOWCASE_I18N_GUIDE.md
• 1 config file: package.json (build scripts)

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How to Add a New Showcase

// showcase-i18n/zh.json
{
  "my-new-showcase": {
    "title": "案例标题",
    "description": "一句话描述",
    "category": "编程开发",
    "features": ["Agent 模式"],
    "thumbnail": "https://...",
    "videoUrl": "https://...",
    "model": "qwen3.5-plus",
    "author": "Qwen Code Team",
    "date": "2025-07-01",
    "overview": "概述文本，支持 Markdown",
    "steps": [
      { "title": "步骤标题", "content": "步骤内容" }
    ],
    "callouts": [
      { "type": "info", "content": "提示信息" }
    ]
  }
}

Then run node scripts/generate-showcase-mdx.js to generate MDX files.

See SHOWCASE_I18N_GUIDE.md for full documentation.

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Testing

• TypeScript compilation passes (0 errors)
• All 39 showcases × 7 languages generate correctly
• Structured JSON → MDX rendering matches original content
• Section headers auto-translated per locale
• Fallback to zh works for missing translations