fix: render consultation replies and typed tool activity

shared/coding-teacher.ts

@@ -83,6 +83,9 @@ export interface TeacherRequest {
   discussionContext?: TeacherDiscussionContext;
   discussionSnapshot?: TeacherDiscussionContent;
   discussionError?: string;
+  /** Original answer retained when discussion parsing fails; never fed back as context. */
+  unparsedResponse?: string;
+  toolActivity?: TeacherToolActivity[];
 
   intent?: TeacherRequestIntent;
   sourceConversationId?: string;
@@ -105,6 +108,11 @@ export interface TeacherRequest {
   cloudRequestId?: string;
   progress?: string;
 }
+export interface TeacherToolActivity {
+  id: string;
+  name: string;
+  status: 'running' | 'completed' | 'failed';
+}
 export interface TeacherTopic {
   discussion?: TeacherDiscussion;
   role?: LegacyConsultationRole;