feat(skills): 技能管理 - 支持后台维护一级分类 (#694)

Co-authored-by: ddcat666 <26564566+ddcat666@users.noreply.github.com>

backend/internal/handler/skill_curation_test.go

@@ -22,6 +22,9 @@ func TestSkillCurationHTTP(t *testing.T) {
 		t.Fatal(err)
 	}
 	sqlDB, _ := db.DB()
+	if err := db.AutoMigrate(&model.SkillCurationRoot{}, &model.SkillCurationRootAssignment{}); err != nil {
+		t.Fatal(err)
+	}
 	sqlDB.SetMaxOpenConns(1)
 	defer sqlDB.Close()
 	if err := db.AutoMigrate(&model.User{}, &model.AuthSession{}, &model.Skill{}, &model.SkillCurationSetting{}, &model.SkillCurationCategory{}, &model.SkillCurationAssignment{}, &model.AdminAuditEvent{}); err != nil {