feat(i18n): add translations for model configuration UI (#368)

- Add ~40 new translation keys for model-config-dialog and model-selector
- Support English, Chinese, and Japanese translations
- Replace all hardcoded strings with dictionary lookups

lib/i18n/dictionaries/en.json

@@ -202,6 +202,47 @@
         "apiKeyStored": "API keys are stored locally in your browser",
         "test": "Test",
         "validationError": "Validation failed",
-        "addModelFirst": "Add at least one model to validate"
+        "addModelFirst": "Add at least one model to validate",
+        "providers": "Providers",
+        "addProviderHint": "Add a provider to get started",
+        "verified": "Verified",
+        "configuration": "Configuration",
+        "displayName": "Display Name",
+        "awsAccessKeyId": "AWS Access Key ID",
+        "awsSecretAccessKey": "AWS Secret Access Key",
+        "awsRegion": "AWS Region",
+        "selectRegion": "Select region",
+        "apiKey": "API Key",
+        "enterApiKey": "Enter your API key",
+        "enterSecretKey": "Enter your secret access key",
+        "baseUrl": "Base URL",
+        "optional": "(optional)",
+        "customEndpoint": "Custom endpoint URL",
+        "models": "Models",
+        "customModelId": "Custom model ID...",
+        "allAdded": "All added",
+        "suggested": "Suggested",
+        "noModelsConfigured": "No models configured",
+        "modelIdEmpty": "Model ID cannot be empty",
+        "modelIdExists": "This model ID already exists",
+        "configureProviders": "Configure AI Providers",
+        "selectProviderHint": "Select a provider from the list or add a new one to configure API keys and models",
+        "deleteConfirmDesc": "Are you sure you want to delete {name}? This will remove all configured models and cannot be undone.",
+        "typeToConfirm": "Type \"{name}\" to confirm",
+        "typeProviderName": "Type provider name...",
+        "modelsConfiguredCount": "{count} model(s) configured",
+        "validationFailedCount": "{count} model(s) failed validation",
+        "cancel": "Cancel",
+        "delete": "Delete",
+        "clickToChange": "(click to change)",
+        "usingServerDefault": "Using server default model",
+        "selectModel": "Select Model",
+        "searchModels": "Search models...",
+        "noVerifiedModels": "No verified models. Test your models first.",
+        "noModelsFound": "No models found.",
+        "default": "Default",
+        "serverDefault": "Server Default",
+        "configureModels": "Configure Models...",
+        "onlyVerifiedShown": "Only verified models are shown"
     }
 }

lib/i18n/dictionaries/ja.json

@@ -202,6 +202,47 @@
         "apiKeyStored": "APIキーはブラウザにローカル保存されます",
         "test": "テスト",
         "validationError": "検証に失敗しました",
-        "addModelFirst": "検証するには少なくとも1つのモデルを追加してください"
+        "addModelFirst": "検証するには少なくとも1つのモデルを追加してください",
+        "providers": "プロバイダー",
+        "addProviderHint": "プロバイダーを追加して開始",
+        "verified": "検証済み",
+        "configuration": "設定",
+        "displayName": "表示名",
+        "awsAccessKeyId": "AWS アクセスキー ID",
+        "awsSecretAccessKey": "AWS シークレットアクセスキー",
+        "awsRegion": "AWS リージョン",
+        "selectRegion": "リージョンを選択",
+        "apiKey": "API キー",
+        "enterApiKey": "API キーを入力",
+        "enterSecretKey": "シークレットアクセスキーを入力",
+        "baseUrl": "ベース URL",
+        "optional": "（オプション）",
+        "customEndpoint": "カスタムエンドポイント URL",
+        "models": "モデル",
+        "customModelId": "カスタムモデル ID...",
+        "allAdded": "すべて追加済み",
+        "suggested": "おすすめ",
+        "noModelsConfigured": "モデルが設定されていません",
+        "modelIdEmpty": "モデル ID は空にできません",
+        "modelIdExists": "このモデル ID は既に存在します",
+        "configureProviders": "AI プロバイダーを設定",
+        "selectProviderHint": "リストからプロバイダーを選択するか、新規追加して API キーとモデルを設定",
+        "deleteConfirmDesc": "{name} を削除してもよろしいですか？設定されたすべてのモデルが削除され、元に戻せません。",
+        "typeToConfirm": "確認のため「{name}」と入力",
+        "typeProviderName": "プロバイダー名を入力...",
+        "modelsConfiguredCount": "{count} 個のモデルを設定済み",
+        "validationFailedCount": "{count} 個のモデルの検証に失敗",
+        "cancel": "キャンセル",
+        "delete": "削除",
+        "clickToChange": "（クリックして変更）",
+        "usingServerDefault": "サーバーデフォルトモデルを使用中",
+        "selectModel": "モデルを選択",
+        "searchModels": "モデルを検索...",
+        "noVerifiedModels": "検証済みのモデルがありません。先にモデルをテストしてください。",
+        "noModelsFound": "モデルが見つかりません。",
+        "default": "デフォルト",
+        "serverDefault": "サーバーデフォルト",
+        "configureModels": "モデルを設定...",
+        "onlyVerifiedShown": "検証済みのモデルのみ表示"
     }
 }

lib/i18n/dictionaries/zh.json

@@ -202,6 +202,47 @@
         "apiKeyStored": "API 密钥存储在您的浏览器本地",
         "test": "测试",
         "validationError": "验证失败",
-        "addModelFirst": "请先添加至少一个模型以进行验证"
+        "addModelFirst": "请先添加至少一个模型以进行验证",
+        "providers": "提供商",
+        "addProviderHint": "添加提供商即可开始使用",
+        "verified": "已验证",
+        "configuration": "配置",
+        "displayName": "显示名称",
+        "awsAccessKeyId": "AWS 访问密钥 ID",
+        "awsSecretAccessKey": "AWS Secret Access Key",
+        "awsRegion": "AWS 区域",
+        "selectRegion": "选择区域",
+        "apiKey": "API 密钥",
+        "enterApiKey": "输入您的 API 密钥",
+        "enterSecretKey": "输入您的 Secret Key",
+        "baseUrl": "基础 URL",
+        "optional": "（可选）",
+        "customEndpoint": "自定义端点 URL",
+        "models": "模型",
+        "customModelId": "自定义模型 ID...",
+        "allAdded": "已全部添加",
+        "suggested": "推荐",
+        "noModelsConfigured": "尚未配置模型",
+        "modelIdEmpty": "模型 ID 不能为空",
+        "modelIdExists": "此模型 ID 已存在",
+        "configureProviders": "配置 AI 提供商",
+        "selectProviderHint": "从列表中选择提供商或添加新的以配置 API 密钥和模型",
+        "deleteConfirmDesc": "确定要删除 {name} 吗？这将移除所有配置的模型且无法撤销。",
+        "typeToConfirm": "输入 \"{name}\" 以确认",
+        "typeProviderName": "输入提供商名称...",
+        "modelsConfiguredCount": "已配置 {count} 个模型",
+        "validationFailedCount": "{count} 个模型验证失败",
+        "cancel": "取消",
+        "delete": "删除",
+        "clickToChange": "（点击更改）",
+        "usingServerDefault": "使用服务器默认模型",
+        "selectModel": "选择模型",
+        "searchModels": "搜索模型...",
+        "noVerifiedModels": "没有已验证的模型。请先测试您的模型。",
+        "noModelsFound": "未找到模型。",
+        "default": "默认",
+        "serverDefault": "服务器默认",
+        "configureModels": "配置模型...",
+        "onlyVerifiedShown": "仅显示已验证的模型"
     }
 }