主要改动：

自动排课接口立即返回 202 + jobId
后台服务独立执行，不受浏览器关闭或前端超时影响
进度、成功、失败状态持久化到数据库
服务重启后自动恢复排队中或中断的任务
同一草稿禁止重复提交后台任务
运行期间禁止编辑、发布或删除该课表
排课结果和任务成功状态在同一事务中提交
前端每秒轮询进度，显示已处理教学班和已规划安排数

src/Jiaowu.Api/Infrastructure/Persistence/DevelopmentSqliteMigrator.cs

@@ -23,6 +23,8 @@ public sealed class DevelopmentSqliteMigrator(
         "20260724_14_scheduling_optimization";
     private const string TeacherCourseApplicationsMigration =
         "20260724_15_teacher_course_applications";
+    private const string AutomaticScheduleJobsMigration =
+        "20260724_16_automatic_schedule_jobs";
 
     public async Task MigrateAsync(CancellationToken cancellationToken = default)
     {
@@ -135,6 +137,18 @@ public sealed class DevelopmentSqliteMigrator(
             TeacherCourseApplicationsMigration,
             teacherCourseApplicationsExist ? [] : TeacherCourseApplicationStatements,
             cancellationToken);
+        var automaticScheduleJobsExist = await db.Database
+            .SqlQueryRaw<int>(
+                """
+                SELECT COUNT(*) AS "Value"
+                FROM sqlite_master
+                WHERE type = 'table' AND name = 'AutomaticScheduleJobs'
+                """)
+            .AnyAsync(value => value > 0, cancellationToken);
+        await ApplyMigrationAsync(
+            AutomaticScheduleJobsMigration,
+            automaticScheduleJobsExist ? [] : AutomaticScheduleJobStatements,
+            cancellationToken);
     }
 
     private async Task ApplyMigrationAsync(
@@ -1022,4 +1036,49 @@ public sealed class DevelopmentSqliteMigrator(
             ON "TeacherCourseApplications" ("ReviewedByUserId");
         """
     ];
+
+    private static readonly string[] AutomaticScheduleJobStatements =
+    [
+        """
+        CREATE TABLE "AutomaticScheduleJobs" (
+            "Id" TEXT NOT NULL CONSTRAINT "PK_AutomaticScheduleJobs" PRIMARY KEY,
+            "SchedulePlanId" TEXT NOT NULL,
+            "ActiveSchedulePlanId" TEXT NULL,
+            "RequestedByUserId" TEXT NULL,
+            "Status" INTEGER NOT NULL,
+            "TotalTasks" INTEGER NOT NULL,
+            "ProcessedTasks" INTEGER NOT NULL,
+            "CreatedEntries" INTEGER NOT NULL,
+            "CompletedTasks" INTEGER NOT NULL,
+            "MessagesJson" TEXT NULL,
+            "ErrorMessage" TEXT NULL,
+            "StartedAt" TEXT NULL,
+            "CompletedAt" TEXT NULL,
+            "CreatedAt" TEXT NOT NULL,
+            "UpdatedAt" TEXT NOT NULL,
+            CONSTRAINT "FK_AutomaticScheduleJobs_SchedulePlans"
+                FOREIGN KEY ("SchedulePlanId") REFERENCES "SchedulePlans" ("Id")
+                ON DELETE CASCADE,
+            CONSTRAINT "FK_AutomaticScheduleJobs_RequestedBy"
+                FOREIGN KEY ("RequestedByUserId") REFERENCES "AspNetUsers" ("Id")
+                ON DELETE SET NULL
+        );
+        """,
+        """
+        CREATE UNIQUE INDEX "IX_AutomaticScheduleJobs_ActiveSchedulePlanId"
+            ON "AutomaticScheduleJobs" ("ActiveSchedulePlanId");
+        """,
+        """
+        CREATE INDEX "IX_AutomaticScheduleJobs_SchedulePlanId_CreatedAt"
+            ON "AutomaticScheduleJobs" ("SchedulePlanId", "CreatedAt");
+        """,
+        """
+        CREATE INDEX "IX_AutomaticScheduleJobs_Status_CreatedAt"
+            ON "AutomaticScheduleJobs" ("Status", "CreatedAt");
+        """,
+        """
+        CREATE INDEX "IX_AutomaticScheduleJobs_RequestedByUserId"
+            ON "AutomaticScheduleJobs" ("RequestedByUserId");
+        """
+    ];
 }