feat: Support i18n

qwen3-tts-frontend/src/locales/en-US/settings.json

@@ -0,0 +1,61 @@
+{
+  "settings": "Settings",
+  "generalSettings": "General Settings",
+  "backendSettings": "Backend Settings",
+  "apiSettings": "API Settings",
+  "preferencesSaved": "Preferences saved",
+  "preferencesSaveFailed": "Preferences save failed",
+  "defaultBackend": "Default Backend",
+  "local": "Local Model",
+  "aliyun": "Aliyun API",
+  "aliyunApiKey": "Aliyun API Key",
+  "apiKeyPlaceholder": "Enter API key",
+  "apiKeyDescription": "Used for Aliyun TTS service authentication",
+  "saveApiKey": "Save Key",
+  "apiKeySaved": "API key saved",
+  "apiKeySaveFailed": "API key save failed",
+  "showApiKey": "Show Key",
+  "hideApiKey": "Hide Key",
+  "testConnection": "Test Connection",
+  "connectionSuccess": "Connection successful",
+  "connectionFailed": "Connection failed",
+  "language": "Interface Language",
+  "languageDescription": "Select interface display language",
+  "theme": "Theme",
+  "themeLight": "Light",
+  "themeDark": "Dark",
+  "themeSystem": "System",
+  "title": "Settings",
+  "description": "Manage your account settings and preferences",
+  "backendPreference": "Backend Preference",
+  "backendPreferenceDescription": "Choose default TTS backend mode",
+  "localModel": "Local Model",
+  "localModelDescription": "Free to use local Qwen3-TTS model",
+  "localModelNoPermission": "Please contact admin to enable local model access",
+  "aliyunApi": "Aliyun API",
+  "aliyunApiDescription": "Use Aliyun TTS service",
+  "switchedToLocal": "Switched to local mode",
+  "switchedToAliyun": "Switched to Aliyun mode",
+  "saveFailed": "Save failed, please retry",
+  "apiKeyUpdated": "API key updated and verified successfully",
+  "apiKeyVerifyFailed": "API key verification failed",
+  "verifyFailed": "Verification failed",
+  "currentStatus": "Current Status:",
+  "configured": "Configured and valid",
+  "notConfigured": "Not configured",
+  "apiKey": "API Key",
+  "updating": "Updating...",
+  "addKey": "Add Key",
+  "updateKey": "Update Key",
+  "verifyKey": "Verify Key",
+  "deleteKey": "Delete Key",
+  "deleteKeyConfirm": "Are you sure you want to delete Aliyun API key? Will switch to local mode automatically.",
+  "keyDeleted": "API key deleted, switched to local mode",
+  "deleteFailed": "Delete failed",
+  "accountInfo": "Account Information",
+  "accountInfoDescription": "Your account basic information",
+  "email": "Email",
+  "changePassword": "Change Password",
+  "passwordChangeSuccess": "Password changed successfully",
+  "passwordChangeFailed": "Password change failed"
+}