教学任务按 授课周数 × 周学时 = 课程总学时 双端校验，不匹配会显示具体差额并阻止保存；公共课批量生成同样校验。

排课约束增加课程、教师、学院、授课方式、场地要求、约束状态筛选，并支持批量修改当前筛选结果。
新增“非排时课程”授课方式：不进入自动排课
不占星期、节次和教室
不阻塞课表发布
允许正常选课
在班级课表和学生个人课表中单独展示

src/Jiaowu.Api/Controllers/CourseSelectionsController.cs

@@ -631,11 +631,12 @@ public sealed class CourseSelectionsController(
                 x.Enrollments.Count(item =>
                     item.Status == CourseEnrollmentStatus.Enrolled),
                 x.IsOpenToAll,
-                x.Enrollments
-                    .Where(item => item.StudentId == student.Id)
-                    .Select(item => (CourseEnrollmentStatus?)item.Status)
-                    .FirstOrDefault(),
-                db.ScheduleEntries
+                 x.Enrollments
+                     .Where(item => item.StudentId == student.Id)
+                     .Select(item => (CourseEnrollmentStatus?)item.Status)
+                     .FirstOrDefault(),
+                 x.TeachingTask.SchedulingMode == TeachingTaskSchedulingMode.Flexible,
+                 db.ScheduleEntries
                     .Where(entry =>
                         entry.TeachingTaskId == x.TeachingTaskId &&
                         entry.SchedulePlan!.AcademicTermId == round.AcademicTermId &&
@@ -803,8 +804,9 @@ public sealed class CourseSelectionsController(
             round.AcademicTermId,
             [task.Id],
             cancellationToken);
-        if (candidateEntries.Count == 0)
-            return ConflictProblem("该教学班尚未发布课表，暂时不能选课。");
+        if (task.SchedulingMode == TeachingTaskSchedulingMode.Standard &&
+            candidateEntries.Count == 0)
+             return ConflictProblem("该教学班尚未发布课表，暂时不能选课。");
         var selectedTaskIds = await db.CourseEnrollments
             .Where(x =>
                 x.StudentId == student.Id &&
@@ -1008,9 +1010,10 @@ public sealed record StudentOfferingDto(
     IEnumerable<string> TeacherNames,
     int Capacity,
     int EnrolledCount,
-    bool IsOpenToAll,
-    CourseEnrollmentStatus? EnrollmentStatus,
-    IEnumerable<StudentScheduleDto> Schedules);
+     bool IsOpenToAll,
+     CourseEnrollmentStatus? EnrollmentStatus,
+     bool IsFlexible,
+     IEnumerable<StudentScheduleDto> Schedules);
 
 public sealed record StudentScheduleDto(
     int DayOfWeek,