feat: enhance localization support for KnowledgeFAQ import and conversation error messages

internal/pkg/i18nx/i18nx_test.go

@@ -104,6 +104,71 @@ func TestTranslateKnownMessageSupportsFormattedMessages(t *testing.T) {
 			message: "登录结果不能为空",
 			want:    "Sign-in result is required.",
 		},
+		{
+			name:    "directory not found",
+			message: "目录不存在",
+			want:    "Directory not found.",
+		},
+		{
+			name:    "directory has docs",
+			message: "该目录下存在文档，无法删除",
+			want:    "This directory contains documents and cannot be deleted.",
+		},
+		{
+			name:    "move documents",
+			message: "请选择要移动的文档",
+			want:    "Select documents to move.",
+		},
+		{
+			name:    "move faqs across knowledge bases",
+			message: "只能移动当前知识库下的FAQ",
+			want:    "Only FAQs in the current knowledge base can be moved.",
+		},
+		{
+			name:    "single knowledge base reference",
+			message: "知识库已被 AI Agent「SalesBot」引用，请先解除绑定",
+			want:    "This knowledge base is referenced by AI Agent \"SalesBot\". Remove the binding first.",
+		},
+		{
+			name:    "multiple knowledge base references",
+			message: "知识库已被 3 个 AI Agent 引用，请先解除绑定",
+			want:    "This knowledge base is referenced by 3 AI Agents. Remove the bindings first.",
+		},
+		{
+			name:    "schedule conflict range",
+			message: "该客服组在 2026-06-02 09:00:00 至 2026-06-02 10:00:00 已存在排班",
+			want:    "This agent team already has a schedule from 2026-06-02 09:00:00 to 2026-06-02 10:00:00.",
+		},
+		{
+			name:    "faq import duplicated question",
+			message: "同一文件中标准问题重复，首次出现于第12行",
+			want:    "The standard question is duplicated in the same file. It first appeared on row 12.",
+		},
+		{
+			name:    "faq import existing question",
+			message: "标准问题已存在，已跳过",
+			want:    "The standard question already exists and was skipped.",
+		},
+		{
+			name:    "required param",
+			message: "参数：name不能为空",
+			want:    "Parameter \"name\" is required.",
+		},
+		{
+			name:    "mcp call failed",
+			message: "调用 MCP 工具失败: timeout",
+			want:    "Failed to call MCP tool: timeout",
+		},
+		{
+			name:    "wxwork unsupported outbound",
+			message: "当前暂不支持企业微信下行消息类型: voice",
+			want:    "The current WeCom outbound message type is not supported yet: voice",
+		},
+		{
+			name:    "wxwork callback missing",
+			message: "企业微信登录回调地址未配置",
+			want:    "WeCom sign-in callback URL is not configured.",
+		},
 	}
 
 	for _, tt := range tests {
@@ -117,6 +182,15 @@ func TestTranslateKnownMessageSupportsFormattedMessages(t *testing.T) {
 	}
 }
 
+func TestTranslateKnownMessageKeepsChineseLocale(t *testing.T) {
+	t.Parallel()
+
+	message := "目录不存在"
+	if got := TranslateKnownMessage(LocaleZhCN, message); got != message {
+		t.Fatalf("TranslateKnownMessage() = %q, want %q", got, message)
+	}
+}
+
 func TestMiddlewareStoresLocale(t *testing.T) {
 	gin.SetMode(gin.TestMode)
 	router := gin.New()