课程库 Excel 导入导出已完成：

支持下载标准导入模板。
导出严格沿用当前关键词、学院、分类、课程性质和状态筛选。
以课程编码为唯一键：存在则更新，不存在则新增。
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。
学院管理员仍只能维护本学院的专业课和实践课，无法借 Excel 越权。
界面入口沿用现有课程库工具栏样式。

src/Jiaowu.Api/Controllers/BaseDataExcelController.cs

@@ -26,7 +26,8 @@ public sealed class BaseDataExcelController(AppDbContext db) : ControllerBase
             ["classes"] = ["编码", "名称", "所属专业编码", "年级", "辅导员工号", "排序", "状态"],
             ["terms"] = ["编码", "名称", "学年", "学期季", "开始日期", "结束日期", "当前学期", "状态"],
             ["buildings"] = ["编码", "名称", "所属校区编码", "排序", "状态"],
-            ["classrooms"] = ["编码", "名称", "所属教学楼编码", "容量", "教室类型", "设备", "排序", "状态"]
+            ["classrooms"] = ["编码", "名称", "所属教学楼编码", "容量", "教室类型", "设备", "排序", "状态"],
+            ["course-categories"] = ["编码", "名称", "排序", "状态"]
         };
 
     [HttpGet("{kind}/template")]
@@ -90,6 +91,8 @@ public sealed class BaseDataExcelController(AppDbContext db) : ControllerBase
                 "terms" => await ImportTermsAsync(rows, errors, cancellationToken),
                 "buildings" => await ImportBuildingsAsync(rows, errors, cancellationToken),
                 "classrooms" => await ImportClassroomsAsync(rows, errors, cancellationToken),
+                "course-categories" => await ImportCourseCategoriesAsync(
+                    rows, errors, cancellationToken),
                 _ => throw new InvalidOperationException()
             };
 
@@ -147,6 +150,10 @@ public sealed class BaseDataExcelController(AppDbContext db) : ControllerBase
                 .OrderBy(x => x.Code).ToListAsync(cancellationToken))
                 .Select(x => Row(x.Code, x.Name, x.Building!.Code, x.Capacity, x.RoomType,
                     x.Equipment, x.SortOrder, Status(x.IsEnabled))).ToList(),
+            "course-categories" => (await db.CourseCategories.AsNoTracking()
+                .OrderBy(x => x.SortOrder).ThenBy(x => x.Code)
+                .ToListAsync(cancellationToken))
+                .Select(x => Row(x.Code, x.Name, x.SortOrder, Status(x.IsEnabled))).ToList(),
             _ => []
         };
 
@@ -471,6 +478,36 @@ public sealed class BaseDataExcelController(AppDbContext db) : ControllerBase
         return new(created, updated, rows.Count);
     }
 
+    private async Task<ExcelImportResult> ImportCourseCategoriesAsync(
+        IReadOnlyList<ExcelRow> rows,
+        List<string> errors,
+        CancellationToken cancellationToken)
+    {
+        var existing = await db.CourseCategories.ToDictionaryAsync(
+            x => x.Code,
+            StringComparer.OrdinalIgnoreCase,
+            cancellationToken);
+        var created = 0;
+        var updated = 0;
+        foreach (var row in rows)
+        {
+            var code = Required(row, "编码", errors);
+            var name = Required(row, "名称", errors);
+            if (code is null || name is null) continue;
+            var entity = existing.GetValueOrDefault(code);
+            if (entity is null)
+            {
+                entity = new CourseCategory { Code = code, Name = name };
+                db.CourseCategories.Add(entity);
+                existing[code] = entity;
+                created++;
+            }
+            else updated++;
+            ApplyCatalog(entity, row, name, errors);
+        }
+        return new(created, updated, rows.Count);
+    }
+
     private ActionResult ImportValidationProblem(IReadOnlyList<string> errors)
     {
         foreach (var error in errors.Take(50))
@@ -582,6 +619,7 @@ public sealed class BaseDataExcelController(AppDbContext db) : ControllerBase
         "terms" => "学期",
         "buildings" => "教学楼",
         "classrooms" => "教室",
+        "course-categories" => "课程分类",
         _ => "基础数据"
     };
 }