“教学班成绩分析”页面新增“定时刷新设置”，支持启停、刷新间隔、单次处理上限、查看上次/下次扫描时间。

配置保存在独立数据库表 CourseGradeStatisticsRefreshSettings，不是修改 appsettings.json。
后台每 10 秒读取配置，仅到期扫描；成绩录入、导入、审批时不再立即创建统计任务。
扫描发现过期数据后，仍通过持久任务、Outbox 和 RabbitMQ 执行；Redis统计缓存由处理任务统一刷新。

src/Jiaowu.Api/Infrastructure/Persistence/Migrations/MySql/20260809123700_CourseGradeStatisticsRefreshSettings.cs

@@ -0,0 +1,48 @@
+using System;
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace Jiaowu.Api.Infrastructure.Persistence.Migrations.MySql
+{
+    /// <inheritdoc />
+    public partial class CourseGradeStatisticsRefreshSettings : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.CreateTable(
+                name: "CourseGradeStatisticsRefreshSettings",
+                columns: table => new
+                {
+                    Id = table.Column<Guid>(type: "char(36)", nullable: false),
+                    Key = table.Column<string>(type: "varchar(50)", maxLength: 50, nullable: false),
+                    IsEnabled = table.Column<bool>(type: "tinyint(1)", nullable: false),
+                    IntervalSeconds = table.Column<int>(type: "int", nullable: false),
+                    BatchSize = table.Column<int>(type: "int", nullable: false),
+                    LastRunAt = table.Column<DateTime>(type: "datetime(6)", nullable: true),
+                    CreatedAt = table.Column<DateTime>(type: "datetime(6)", nullable: false),
+                    UpdatedAt = table.Column<DateTime>(type: "datetime(6)", nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_CourseGradeStatisticsRefreshSettings", x => x.Id);
+                })
+                .Annotation("MySQL:Charset", "utf8mb4");
+
+            migrationBuilder.CreateIndex(
+                name: "IX_CourseGradeStatisticsRefreshSettings_Key",
+                table: "CourseGradeStatisticsRefreshSettings",
+                column: "Key",
+                unique: true);
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropTable(
+                name: "CourseGradeStatisticsRefreshSettings");
+
+        }
+    }
+}

src/Jiaowu.Api/Infrastructure/Persistence/Migrations/MySql/AppDbContextModelSnapshot.cs

@@ -1098,6 +1098,43 @@ namespace Jiaowu.Api.Infrastructure.Persistence.Migrations.MySql
                     b.ToTable("CourseGradeStatisticsRefreshJobs");
                 });
 
+            modelBuilder.Entity("Jiaowu.Api.Domain.Academic.CourseGradeStatisticsRefreshSetting", b =>
+                {
+                    b.Property<Guid>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("char(36)");
+
+                    b.Property<int>("BatchSize")
+                        .HasColumnType("int");
+
+                    b.Property<DateTime>("CreatedAt")
+                        .HasColumnType("datetime(6)");
+
+                    b.Property<int>("IntervalSeconds")
+                        .HasColumnType("int");
+
+                    b.Property<bool>("IsEnabled")
+                        .HasColumnType("tinyint(1)");
+
+                    b.Property<string>("Key")
+                        .IsRequired()
+                        .HasMaxLength(50)
+                        .HasColumnType("varchar(50)");
+
+                    b.Property<DateTime?>("LastRunAt")
+                        .HasColumnType("datetime(6)");
+
+                    b.Property<DateTime>("UpdatedAt")
+                        .HasColumnType("datetime(6)");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("Key")
+                        .IsUnique();
+
+                    b.ToTable("CourseGradeStatisticsRefreshSettings");
+                });
+
             modelBuilder.Entity("Jiaowu.Api.Domain.Academic.CourseGroup", b =>
                 {
                     b.Property<Guid>("Id")