feat(coding): keep one ongoing conversation per delivered agent

shared/coding-teacher.ts

@@ -74,12 +74,19 @@ export interface TeacherDiscussionContext {
   transition?: 'structure';
 }
 export interface TeacherDiscussionAction {
+  projectId?: string;
   toolId: string;
   revision: number;
   action: 'enter' | 'pause' | 'finish' | 'resume' | 'keep-idea' | 'aside-idea' | 'first-idea' | 'back-ideas';
   itemId?: string;
 }
 export interface TeacherRequest {
+  /** Frozen when this turn is accepted; history can span projects and releases. */
+  projectId?: string;
+  projectName?: string;
+  teacherVersion?: number;
+  runtimeThreadId?: string;
+  origin?: { projectId: string; topicId: string; requestId: string };
   presentation?: 'discussion-v1';
   discussionContext?: TeacherDiscussionContext;
   discussionSnapshot?: TeacherDiscussionContent;
@@ -115,6 +122,14 @@ export interface TeacherToolActivity {
   status: 'running' | 'completed' | 'failed';
 }
 export interface TeacherTopic {
+  /** Present only for the account-owned continuous conversation. */
+  conversation?: {
+    agentId: string;
+    runtimeThreadId?: string;
+    segmentTurns: number;
+    discussions: Record<string, TeacherDiscussion>;
+    seenThrough?: string;
+  };
   discussion?: TeacherDiscussion;
   role?: LegacyConsultationRole;
   revision: number;
@@ -132,10 +147,11 @@ export interface TeacherTopic {
   unsaved?: boolean;
 }
 export interface TeacherTopicList {
-  items: Array<{ id: string; title: string; updatedAt: string; version: number; teacherId?: string; legacyRole?: 'friend' }>;
+  items: Array<{ id: string; title: string; updatedAt: string; version: number; teacherId?: string; legacyRole?: 'friend'; legacySourceId?: string }>;
   lastSelectedTopicId: string | null;
 }
 export interface TeacherSend {
+  projectId?: string;
   presentation?: 'discussion-v1';
   discussion?: TeacherDiscussionContext;
   intent?: TeacherRequestIntent;
@@ -144,6 +160,14 @@ export interface TeacherSend {
   text: string;
   references?: TeacherReference[];
 }
+export interface TeacherHistoryPage {
+  requests: TeacherRequest[];
+  before: string | null;
+}
+export interface TeacherConversationView {
+  topic: TeacherTopic | null;
+  before: string | null;
+}
 export interface TeacherCheckInInput {
   requestId: string;
   sourceConversationId: string;