优化发布群租客清退与历史消息

backend/internal/modules/systemconfig/repository.go

@@ -38,6 +38,7 @@ var defaultConfigs = []defaultConfig{
 	{Key: "chat.default_support_admin_id", Value: "2", Description: "默认客服 ID（必须是启用状态的客服角色）"},
 	{Key: "chat.auto_welcome_message", Value: "欢迎加入订单群聊！如有任何问题，请随时沟通。", Description: "建群后自动发送的欢迎话术"},
 	{Key: "chat.listing_group_welcome", Value: "欢迎加入账号群！请号主扫描下方二维码加入企业微信群，方便客服与您及时联系。", Description: "发布群创建后自动发送的欢迎语"},
+	{Key: "chat.renter_retention_days_after_order_end", Value: "5", Description: "订单结束后租客保留在发布群的天数（3-7）"},
 	{Key: homeAnnouncementsConfigKey, Value: defaultHomeAnnouncementsConfigValue(), Description: "移动端首页公告 JSON 数组"},
 	{Key: homeBannersConfigKey, Value: defaultHomeBannersConfigValue(), Description: "移动端首页轮播图 JSON 数组"},
 	{Key: publishOptionsConfigKey, Value: defaultPublishOptionsConfigValue(), Description: "发布页选项配置 JSON"},
@@ -48,6 +49,7 @@ var adminVisibleConfigKeys = []string{
 	"chat.auto_welcome_message",
 	"chat.default_support_admin_id",
 	"chat.listing_group_welcome",
+	"chat.renter_retention_days_after_order_end",
 	"handoff.owner_return_confirm_timeout_minutes",
 	"handoff.owner_submit_timeout_minutes",
 	"handoff.renter_confirm_timeout_minutes",