fix(teacher): 独立刷新老师目录以缩短配置更新延迟

shared/coding-teacher.ts

@@ -40,6 +40,7 @@ export interface TeacherAvailability {
   revision: number;
 }
 export interface TeacherCatalog {
+  revision?: number;
   items: Array<{ teacher_id: string; version: number; definition: TeacherDefinition; is_default: boolean }>;
 }
 export interface TeacherReference {