课程库 Excel 导入导出已完成：

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校验学院编码、课程分类、课程性质、学分学时及考核方式。
整批原子导入，任一行错误则全部不写入，并提示具体行号。
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src/Jiaowu.Api/Controllers/GraduationAuditsController.cs

@@ -156,10 +156,6 @@ public sealed class GraduationAuditsController(
         {
             var plan = plans.FirstOrDefault(x =>
                 x.MajorId == student.AdministrativeClass!.MajorId);
-            var requiredCourses = plan?.Modules
-                .SelectMany(x => x.Courses)
-                .Where(x => x.Type == CurriculumCourseType.Required)
-                .ToList() ?? [];
             var studentGrades = grades.Where(x => x.StudentId == student.Id).ToList();
             var passedCourseIds = studentGrades
                 .Where(IsPassed)
@@ -170,14 +166,12 @@ public sealed class GraduationAuditsController(
                 .Where(IsPassed)
                 .GroupBy(x => x.CourseId)
                 .Sum(x => x.Max(item => item.Credits));
-            var missingCourses = requiredCourses
-                .Where(x => !passedCourseIds.Contains(x.CourseId))
-                .Select(x => x.Course!.Name)
-                .Distinct()
-                .ToArray();
+            var completion = CurriculumCompletionRules.Evaluate(
+                plan?.Modules ?? [],
+                passedCourseIds);
             var missingCourseNames = plan is null
                 ? "未匹配已发布的培养方案"
-                : string.Join("、", missingCourses);
+                : string.Join("、", completion.MissingRequirements);
             if (missingCourseNames.Length > 2000)
                 missingCourseNames = missingCourseNames[..2000];
             var failedCourseCount = studentGrades
@@ -188,8 +182,8 @@ public sealed class GraduationAuditsController(
                 student.Status,
                 plan?.TotalCredits ?? 0,
                 earnedCredits,
-                requiredCourses.Count,
-                requiredCourses.Count - missingCourses.Length,
+                completion.RequirementCount,
+                completion.PassedRequirementCount,
                 failedCourseCount);
             db.GraduationAuditResults.Add(new GraduationAuditResult
             {
@@ -199,8 +193,8 @@ public sealed class GraduationAuditsController(
                 StudentStatusSnapshot = student.Status,
                 RequiredCredits = plan?.TotalCredits ?? 0,
                 EarnedCredits = earnedCredits,
-                RequiredCourseCount = requiredCourses.Count,
-                PassedRequiredCourseCount = requiredCourses.Count - missingCourses.Length,
+                RequiredCourseCount = completion.RequirementCount,
+                PassedRequiredCourseCount = completion.PassedRequirementCount,
                 FailedCourseCount = failedCourseCount,
                 MissingCourseNames = missingCourseNames,
                 CalculatedConclusion = conclusion,