成绩通知：仅在某门课程成绩正式发布后自动发送，按成绩单学生名单通知，不展示具体分数；发布状态与通知同一次提交。

手动发信：移除“成绩通知”选项，只能发送普通通知，原有角色与范围权限保持不变。
选课通知：管理员关闭一轮选课时，自动向每位参与学生发送一条汇总通知，包含最终选中课程及候补未成功课程；候补失效、轮次关闭和通知生成保持原子性。
关闭选课界面会明确提示发送通知，并显示实际通知人数。

src/Jiaowu.Api/Controllers/CourseSelectionsController.cs

@@ -218,38 +218,67 @@ public sealed class CourseSelectionsController(
                 if (round.Status != CourseSelectionRoundStatus.Open)
                     return ConflictProblem("只有开放中的选课批次可以关闭。");
 
-                var waitlisted = await db.CourseEnrollments
+                var enrollments = await db.CourseEnrollments
                     .Include(x => x.Student)
                     .Include(x => x.CourseSelectionOffering)
                     .ThenInclude(x => x!.TeachingTask)
                     .ThenInclude(x => x!.Course)
                     .Where(x =>
-                        x.CourseSelectionOffering!.CourseSelectionRoundId == id &&
-                        x.Status == CourseEnrollmentStatus.Waitlisted)
+                        x.CourseSelectionOffering!.CourseSelectionRoundId == id)
                     .ToListAsync(cancellationToken);
+                var waitlisted = enrollments
+                    .Where(x => x.Status == CourseEnrollmentStatus.Waitlisted)
+                    .ToList();
                 var now = DateTime.UtcNow;
                 foreach (var enrollment in waitlisted)
                 {
                     enrollment.Status = CourseEnrollmentStatus.Expired;
                     enrollment.WithdrawnAt = now;
-                    if (enrollment.Student!.UserId is Guid userId)
+                }
+
+                var participantGroups = enrollments
+                    .Where(x => x.Student!.UserId.HasValue)
+                    .GroupBy(x => new
                     {
-                        db.Notifications.Add(new Notification
-                        {
-                            UserId = userId,
-                            Title = "课程候补已结束",
-                            Content =
-                                $"“{enrollment.CourseSelectionOffering!.TeachingTask!.Course!.Name}”" +
-                                "选课批次已关闭，本次候补未获得名额。",
-                            LinkUrl = "/course-selections"
-                        });
-                    }
+                        x.StudentId,
+                        UserId = x.Student!.UserId!.Value
+                    })
+                    .ToList();
+                foreach (var participant in participantGroups)
+                {
+                    var selectedCourses = participant
+                        .Where(x => x.Status == CourseEnrollmentStatus.Enrolled)
+                        .Select(x => x.CourseSelectionOffering!.TeachingTask!.Course!.Name)
+                        .Distinct()
+                        .OrderBy(x => x)
+                        .ToArray();
+                    var unsuccessfulCourses = participant
+                        .Where(x => x.Status == CourseEnrollmentStatus.Expired)
+                        .Select(x => x.CourseSelectionOffering!.TeachingTask!.Course!.Name)
+                        .Distinct()
+                        .OrderBy(x => x)
+                        .ToArray();
+                    db.Notifications.Add(new Notification
+                    {
+                        UserId = participant.Key.UserId,
+                        Title = $"{round.Name}结果",
+                        Content = BuildRoundResultContent(
+                            round.Name,
+                            selectedCourses,
+                            unsuccessfulCourses),
+                        Category = NotificationCategory.CourseSelection,
+                        LinkUrl = "/course-selections"
+                    });
                 }
 
                 round.Status = CourseSelectionRoundStatus.Closed;
                 await db.SaveChangesAsync(cancellationToken);
                 await transaction.CommitAsync(cancellationToken);
-                return Ok(new { ExpiredWaitlistCount = waitlisted.Count });
+                return Ok(new
+                {
+                    ExpiredWaitlistCount = waitlisted.Count,
+                    NotifiedStudentCount = participantGroups.Count
+                });
             },
             cancellationToken,
             IsolationLevel.Serializable);
@@ -940,6 +969,7 @@ public sealed class CourseSelectionsController(
                         Content =
                             $"管理员已将你移出“{enrollment.CourseSelectionOffering!.TeachingTask!.Course!.Name}”" +
                             "候补队列。",
+                        Category = NotificationCategory.CourseSelection,
                         LinkUrl = "/course-selections"
                     });
                 }
@@ -1835,6 +1865,7 @@ public sealed class CourseSelectionsController(
                         Content =
                             $"“{offering.TeachingTask!.Course!.Name}”候补未能递补：" +
                             eligibility.Error,
+                        Category = NotificationCategory.CourseSelection,
                         LinkUrl = "/course-selections"
                     });
                 }
@@ -1869,6 +1900,7 @@ public sealed class CourseSelectionsController(
                     Content =
                         $"“{offering.TeachingTask.Course!.Name}”已释放名额，" +
                         "你已自动进入正式选课名单。",
+                    Category = NotificationCategory.CourseSelection,
                     LinkUrl = "/course-selections"
                 });
             }
@@ -1918,6 +1950,39 @@ public sealed class CourseSelectionsController(
         }
     }
 
+    private static string BuildRoundResultContent(
+        string roundName,
+        IReadOnlyCollection<string> selectedCourses,
+        IReadOnlyCollection<string> unsuccessfulCourses)
+    {
+        var parts = new List<string> { $"{roundName}已结束。" };
+        parts.Add(selectedCourses.Count == 0
+            ? "本轮未选中课程。"
+            : $"最终选中 {selectedCourses.Count} 门：{FormatCourseNames(selectedCourses)}。");
+        if (unsuccessfulCourses.Count > 0)
+        {
+            parts.Add(
+                $"候补未成功 {unsuccessfulCourses.Count} 门：" +
+                $"{FormatCourseNames(unsuccessfulCourses)}。");
+        }
+
+        return string.Concat(parts);
+    }
+
+    private static string FormatCourseNames(IReadOnlyCollection<string> courses)
+    {
+        const int visibleCount = 8;
+        const int visibleNameLength = 40;
+        var names = courses.Take(visibleCount)
+            .Select(name => name.Length <= visibleNameLength
+                ? $"《{name}》"
+                : $"《{name[..visibleNameLength]}…》");
+        var result = string.Join("、", names);
+        return courses.Count > visibleCount
+            ? $"{result}等 {courses.Count} 门课程"
+            : result;
+    }
+
     private ActionResult ProfileNotFound() =>
         ConflictProblem("当前账号未关联有效学生档案，请联系教务管理员。");