fix(s8): reserve empty dashboard scene distribution

server/Plugins/Admin.NET.Plugin.AiDOP/Service/S8/S8DashboardService.cs

@@ -124,9 +124,10 @@ public class S8DashboardService : ITransient
             byStatus = list
                 .GroupBy(x => x.Status)
                 .Select(g => new { key = g.Key, count = g.Count() }),
-            byScene = list
-                .GroupBy(x => x.SceneCode)
-                .Select(g => new { key = g.Key, count = g.Count() }),
+            // S8-DASHBOARD-BYSCENE-RESERVE-CLEAR-1：byScene 不再生成。
+            // 业务展示主口径已切到 module_code（byProcess），保留 scene_code 仅用于建单/规则唯一性/配置 CRUD/历史追溯。
+            // 字段保留以维持响应结构兼容；前端无消费方。
+            byScene = Array.Empty<object>(),
             // S8-SEVERITY-FOLLOW-SERIOUS-STANDARDIZE-EXEC-1：bySeverity 归一为 FOLLOW/SERIOUS 两桶。
             bySeverity = list
                 .GroupBy(x => S8SeverityCode.Normalize(x.Severity))