FIX: Add missing i18n translation for admin.encryptionEnabled

Added missing translation key for database security settings:

Problem:
- AdminSettings.tsx used t("admin.encryptionEnabled")
- Translation key was missing from both English and Chinese files
- Caused missing text in database security encryption status display

Solution:
- Added "encryptionEnabled": "Encryption Enabled" to English translations
- Added "encryptionEnabled": "加密已启用" to Chinese translations
- Maintains consistency with existing encryption-related translations

Files updated:
- src/locales/en/translation.json
- src/locales/zh/translation.json

Now the database security section properly displays encryption status
with correct i18n support in both languages.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/locales/en/translation.json

@@ -377,6 +377,7 @@
     "overrideUserInfoUrl": "Override User Info URL (not required)",
     "databaseSecurity": "Database Security",
     "encryptionStatus": "Encryption Status",
+    "encryptionEnabled": "Encryption Enabled",
     "enabled": "Enabled",
     "disabled": "Disabled",
     "keyId": "Key ID",

src/locales/zh/translation.json

@@ -363,6 +363,7 @@
     "overrideUserInfoUrl": "覆盖用户信息 URL（非必填）",
     "databaseSecurity": "数据库安全",
     "encryptionStatus": "加密状态",
+    "encryptionEnabled": "加密已启用",
     "enabled": "已启用",
     "disabled": "已禁用",
     "keyId": "密钥 ID",