自动排课：保留手工安排，按教师、行政班、周次、节次、容量和场地约束补排。

课程约束：可限定校区、教学楼、指定教室、允许上课日、最早/最晚节次。
无教室课程：教室可为空，但仍校验教师和班级冲突。
作息维护：按学期维护节次、上下课时间和启用状态。
发布保护：发布前重新检查全部约束，并阻止学时未排满的课表发布。
工作台升级：增加“排课规则与作息”“自动排课”入口，自动生成后仍支持手工微调。
同时兼容 SQLite 和 MySQL，已生成正式迁移。

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

@@ -29,6 +29,11 @@ public sealed class AppDbContext(DbContextOptions<AppDbContext> options)
     public DbSet<TeachingTaskClass> TeachingTaskClasses => Set<TeachingTaskClass>();
     public DbSet<SchedulePlan> SchedulePlans => Set<SchedulePlan>();
     public DbSet<ScheduleEntry> ScheduleEntries => Set<ScheduleEntry>();
+    public DbSet<ScheduleTimeSlot> ScheduleTimeSlots => Set<ScheduleTimeSlot>();
+    public DbSet<TeachingTaskScheduleConstraint> TeachingTaskScheduleConstraints =>
+        Set<TeachingTaskScheduleConstraint>();
+    public DbSet<TeachingTaskAllowedClassroom> TeachingTaskAllowedClassrooms =>
+        Set<TeachingTaskAllowedClassroom>();
     public DbSet<CourseSelectionRound> CourseSelectionRounds =>
         Set<CourseSelectionRound>();
     public DbSet<CourseSelectionOffering> CourseSelectionOfferings =>
@@ -293,6 +298,51 @@ public sealed class AppDbContext(DbContextOptions<AppDbContext> options)
                 .WithMany()
                 .HasForeignKey(x => x.TeachingTaskId)
                 .OnDelete(DeleteBehavior.Restrict);
+            entity.HasOne(x => x.Classroom)
+                .WithMany()
+                .HasForeignKey(x => x.ClassroomId)
+                .OnDelete(DeleteBehavior.SetNull);
+        });
+
+        builder.Entity<ScheduleTimeSlot>(entity =>
+        {
+            entity.Property(x => x.Name).HasMaxLength(40);
+            entity.HasIndex(x => new { x.AcademicTermId, x.PeriodNumber }).IsUnique();
+            entity.HasOne(x => x.AcademicTerm)
+                .WithMany()
+                .HasForeignKey(x => x.AcademicTermId)
+                .OnDelete(DeleteBehavior.Cascade);
+        });
+
+        builder.Entity<TeachingTaskScheduleConstraint>(entity =>
+        {
+            entity.Property(x => x.AllowedDayOfWeeks).HasMaxLength(20);
+            entity.HasIndex(x => x.TeachingTaskId).IsUnique();
+            entity.HasOne(x => x.TeachingTask)
+                .WithMany()
+                .HasForeignKey(x => x.TeachingTaskId)
+                .OnDelete(DeleteBehavior.Cascade);
+            entity.HasOne(x => x.RequiredCampus)
+                .WithMany()
+                .HasForeignKey(x => x.RequiredCampusId)
+                .OnDelete(DeleteBehavior.Restrict);
+            entity.HasOne(x => x.RequiredBuilding)
+                .WithMany()
+                .HasForeignKey(x => x.RequiredBuildingId)
+                .OnDelete(DeleteBehavior.Restrict);
+        });
+
+        builder.Entity<TeachingTaskAllowedClassroom>(entity =>
+        {
+            entity.HasKey(x => new
+            {
+                x.TeachingTaskScheduleConstraintId,
+                x.ClassroomId
+            });
+            entity.HasOne(x => x.TeachingTaskScheduleConstraint)
+                .WithMany(x => x.AllowedClassrooms)
+                .HasForeignKey(x => x.TeachingTaskScheduleConstraintId)
+                .OnDelete(DeleteBehavior.Cascade);
             entity.HasOne(x => x.Classroom)
                 .WithMany()
                 .HasForeignKey(x => x.ClassroomId)