feat: 擴展 i18n 支援 65 種語言 + 完整文件系統

🌐 國際化 (i18n)
- 從 5 種語言擴展到 65 種語言支援
- 新增：歐洲語系 (de, fr, es, it, pt, ru, nl, pl, tr, uk, cs, sv, da, fi, no, el, hu, ro, bg, hr, sk, sl, lt, lv, et, is, ga, cy, mt, mk, sq, ca, eu, gl, sr)
- 新增：中東語系 (ar, he, fa)
- 新增：南亞語系 (hi, bn, ta, te, mr, gu, kn, ml, ne, si)
- 新增：東南亞語系 (th, vi, id, ms, fil, my, km, lo)
- 新增：非洲語系 (af, sw, am, zu)
- 完整翻譯所有 UI 文字

📖 文件系統
- 重構 README.md 為入口型首頁
- 新增 docs/getting-started.md - 快速入門指南
- 新增 docs/docker.md - Docker 部署指南
- 新增 docs/environment-variables.md - 環境變數說明
- 新增 docs/url-id-and-storage.md - 儲存結構說明
- 新增 docs/advanced-usage.md - 進階使用指南
- 更新 docs/i18n.md - 65 種語言清單

✅ 建構驗證
- TypeScript 編譯通過
- Docker 建構通過

src/locales/sw.json

@@ -0,0 +1,106 @@
+{
+  "common": {
+    "appName": "ConvertX-CN",
+    "poweredBy": "Inayoendeshwa na",
+    "version": "v{version}",
+    "loading": "Inapakia...",
+    "error": "Hitilafu",
+    "success": "Imefanikiwa",
+    "confirm": "Thibitisha",
+    "cancel": "Ghairi",
+    "close": "Funga",
+    "save": "Hifadhi",
+    "delete": "Futa",
+    "remove": "Ondoa",
+    "download": "Pakua",
+    "upload": "Pakia",
+    "submit": "Wasilisha",
+    "back": "Rudi",
+    "next": "Inayofuata",
+    "yes": "Ndiyo",
+    "no": "Hapana"
+  },
+  "nav": {
+    "history": "Historia",
+    "account": "Akaunti",
+    "logout": "Toka",
+    "login": "Ingia",
+    "register": "Jisajili",
+    "language": "Lugha"
+  },
+  "convert": {
+    "title": "Badilisha",
+    "titleWithType": "Badilisha .{fileType}",
+    "chooseFile": "Chagua faili",
+    "orDragHere": "au iburute hapa",
+    "searchConversions": "Tafuta ubadilishaji",
+    "convertTo": "Badilisha kuwa",
+    "convertButton": "Badilisha",
+    "uploading": "Inapakia...",
+    "processing": "Inachakata..."
+  },
+  "results": {
+    "title": "Matokeo",
+    "convertedFileName": "Jina la faili iliyobadilishwa",
+    "status": "Hali",
+    "actions": "Vitendo",
+    "downloadAll": "Zote",
+    "downloadTar": "Tar",
+    "deleteJob": "Futa",
+    "noFiles": "Hakuna faili zilizobadilishwa bado.",
+    "statusPending": "Inasubiri",
+    "statusCompleted": "Imekamilika",
+    "statusFailed": "Imeshindwa"
+  },
+  "history": {
+    "title": "Matokeo",
+    "time": "Wakati",
+    "files": "Faili",
+    "filesDone": "Faili zilizokamilika",
+    "status": "Hali",
+    "actions": "Vitendo",
+    "expandDetails": "Panua maelezo",
+    "detailedFileInfo": "Maelezo ya kina ya faili:",
+    "deleteSelected": "Futa zilizochaguliwa",
+    "selectAll": "Chagua zote",
+    "confirmDelete": "Una uhakika unataka kufuta kazi {count}? Kitendo hiki hakiwezi kutenduliwa.",
+    "deleteSuccess": "Kazi {deleted} zimefutwa kwa mafanikio.",
+    "deleteFailed": "Imeshindwa kufuta kazi {failed}.",
+    "deleteError": "Hitilafu imetokea wakati wa kufuta kazi. Tafadhali jaribu tena."
+  },
+  "auth": {
+    "email": "Barua pepe",
+    "password": "Nenosiri",
+    "currentPassword": "Nenosiri la sasa",
+    "newPassword": "Nenosiri (acha tupu ikiwa halijabadilishwa)",
+    "loginButton": "Ingia",
+    "registerButton": "Jisajili",
+    "updateButton": "Sasisha",
+    "createAccount": "Unda akaunti",
+    "invalidCredentials": "Vitambulisho batili.",
+    "emailInUse": "Barua pepe tayari inatumika.",
+    "unauthorized": "Haujaidhinishwa",
+    "cookiesRequired": "Kuki zinapaswa kuwezeshwa kutumia programu hii.",
+    "noCookies": "Hakuna kuki ya uthibitisho, labda kivinjari chako kinazuia kuki."
+  },
+  "setup": {
+    "welcome": "Karibu kwenye ConvertX-CN!",
+    "createYourAccount": "Unda akaunti yako",
+    "reportIssues": "Ripoti matatizo yoyote kwenye",
+    "github": "GitHub"
+  },
+  "errors": {
+    "jobNotFound": "Kazi haijapatikana.",
+    "fileNotFound": "Faili haijapatikana.",
+    "uploadFailed": "Upakiaji umeshindwa.",
+    "conversionFailed": "Ubadilishaji umeshindwa.",
+    "serverError": "Hitilafu ya seva."
+  },
+  "upload": {
+    "success": "Faili zimepakiwa kwa mafanikio.",
+    "dragDrop": "Dondosha faili hapa"
+  },
+  "file": {
+    "size": "{size} kB"
+  }
+}