feat(i18n): add multi-language support with next-intl (#1775)

1. Integrate next-intl/routing for locale-based routing
2. Add translation files for Chinese, English, and Japanese
3. Replace hardcoded Chinese strings with translation keys across components
4. Implement LocaleSwitcherFAB for language switching in footer
5. Update middleware to handle Accept-Language header and locale cookies
6. Migrate all pages to [locale]/ route structure
7. Replace next/link with enhanced Link/Router for locale-aware navigation

Author: ttimochan

.env.example

@@ -1,4 +1,7 @@
 NEXT_PUBLIC_API_URL=http://127.0.0.1:2333/api/v2
 NEXT_PUBLIC_GATEWAY_URL=http://127.0.0.1:2333
 NEXT_PUBLIC_SNIPPET_NAME=kami
+NEXT_PUBLIC_KAMI_LOCALES=zh,en
+# Comma-separated locale codes (zh,en,ja). Omit or leave empty to enable all. Must include zh.
+# NEXT_PUBLIC_KAMI_LOCALES=zh,en
 ASSETPREFIX=

.eslintrc.js

@@ -1,10 +1,17 @@
 module.exports = {
   extends: ['@innei/eslint-config-react-ts'],
+  settings: {
+    react: {
+      version: 'detect',
+    },
+  },
   rules: {
     '@typescript-eslint/no-empty-function': 'off',
     '@typescript-eslint/no-empty-interface': 'off',
     '@typescript-eslint/no-non-null-assertion': 'off',
     'no-restricted-globals': ['error', 'close', 'open', 'name', 'event'],
+    'react/display-name': 'off',
+    'react-hooks/exhaustive-deps': 'off',
     'react/self-closing-comp': 'warn',
     'react/jsx-curly-brace-presence': [
       'error',

.github/workflows/nextjs_bundle_analysis.yml

@@ -59,7 +59,7 @@ jobs:
         run: npx -p nextjs-bundle-analysis report
 
       - name: Upload bundle
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: bundle
           path: .next/analyze/__bundle_analysis.json
@@ -78,7 +78,7 @@ jobs:
 
       - name: Upload analysis
         if: success() && github.event.number
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: analysis_comment
           path: .next/analyze/__bundle_analysis_comment.txt
@@ -89,7 +89,7 @@ jobs:
 
       - name: Upload PR number
         if: ${{ always() }}
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: pr
           path: ./pr-id.txt

package.json

@@ -60,7 +60,7 @@
   "dependencies": {
     "@floating-ui/react-dom": "2.0.2",
     "@formkit/auto-animate": "1.0.0-beta.6",
-    "@mx-space/api-client": "1.13.1",
+    "@mx-space/api-client": "2.0.0",
     "@sentry/nextjs": "7.74.1",
     "axios": "1.5.1",
     "clsx": "2.0.0",
@@ -75,6 +75,7 @@
     "medium-zoom": "1.0.8",
     "mermaid": "10.5.0",
     "next": "13.5.3",
+    "next-intl": "^4.7.0",
     "next-seo": "6.1.0",
     "next-suspense": "0.2.3",
     "randomcolor": "0.6.2",
@@ -108,7 +109,7 @@
     "@types/markdown-escape": "1.1.2",
     "@types/node": "20.8.6",
     "@types/randomcolor": "0.5.8",
-    "@types/react": "17.0.68",
+    "@types/react": "18.2.13",
     "@types/react-color": "3.0.9",
     "@types/react-dom": "18.2.13",
     "@types/remove-markdown": "0.3.3",