fix: preserve complete consultation replies and recover retained history

electron/coding-teacher/context.ts

@@ -62,12 +62,12 @@ export function teacherHistoryMessages(history: TeacherRequest[]): TeacherSource
       id: 'teacher:' + request.id + ':user', role: 'user' as const,
       text: [...request.references.map(ref => '明确引用：\n' + ref.text), request.text].join('\n\n'),
     }]),
-    {
+    ...(request.replyIncomplete ? [] : [{
       id: 'teacher:' + request.id + ':assistant', role: 'assistant' as const,
       text: [request.response, ...(request.suggestedQuestions?.length
         ? ['可以接着聊的问题：\n' + request.suggestedQuestions.map(text => '- ' + text).join('\n')]
         : [])].join('\n\n'),
-    },
+    }]),
   ]);
 }
 // A bounded text estimate for the native model path, not an exact tokenizer or

electron/coding-teacher/reply.ts

@@ -2,7 +2,7 @@ import type { TeacherRequest } from '../../shared/coding-teacher';
 import { parseTeacherReply } from '../../shared/teacher-reply';
 
 export function teacherReplyInstructions(): string {
-  return '本轮界面接收一个 JSON 对象 {"reply":string,"quickReplies":string[]}。reply 是回复正文，可使用 Markdown；quickReplies 是可选的后续回复建议，没有建议时用空数组。只使用这两个字段。依据已配置职责帮助学生整理想法、理解关系、承接已确认的共识；区分学生已确认内容与智能体建议、待定想法。回复的语言、风格、长度、前缀和建议内容遵循当前智能体的云端配置。';
+  return '本轮界面接收一个 JSON 对象 {"reply":string,"quickReplies":string[]}。reply 是回复正文，可使用 Markdown；quickReplies 是可选的后续回复建议，没有建议时用空数组。只使用这两个字段。字符串中的英文双引号、反斜杠和换行必须按 JSON 规则转义，确保整个对象是合法 JSON。依据已配置职责帮助学生整理想法、理解关系、承接已确认的共识；区分学生已确认内容与智能体建议、待定想法。回复的语言、风格、长度、前缀和建议内容遵循当前智能体的云端配置。';
 }
 
 /** The original response remains available for diagnosis when parsing is incomplete. */
@@ -10,11 +10,14 @@ export function applyTeacherReply(request: TeacherRequest, raw: string): void {
   const parsed = parseTeacherReply(raw);
   request.response = parsed.reply;
   request.suggestedQuestions = parsed.quickReplies;
+  if (parsed.incomplete) request.replyIncomplete = true;
+  else delete request.replyIncomplete;
   if (parsed.parseError) {
     request.replyParseError = parsed.parseError;
-    request.unparsedResponse = raw;
   } else {
     delete request.replyParseError;
-    delete request.unparsedResponse;
+    delete request.discussionError;
   }
+  if (parsed.parseError || parsed.recovered) request.unparsedResponse = raw;
+  else delete request.unparsedResponse;
 }

electron/coding-teacher/store.ts

@@ -1,9 +1,40 @@
 import { mkdir, readdir } from 'node:fs/promises';
 import path from 'node:path';
 import { atomicWriteJson, readJsonFile } from '../coding-projects/atomic-json';
-import type { TeacherTopic, TeacherTopicList } from '../../shared/coding-teacher';
+import type { TeacherRequest, TeacherTopic, TeacherTopicList } from '../../shared/coding-teacher';
+import { isTeacherReplyEnvelope, parseTeacherReply } from '../../shared/teacher-reply';
 import { TeacherError } from './config-client';
 
+/** Repair only received, completed protocol replies; never resume a model request. */
+function repairCompletedReply(request: TeacherRequest): void {
+  const raw = request.unparsedResponse;
+  if (request.status !== 'completed' || typeof raw !== 'string'
+    || !(request.discussionError || request.replyParseError || request.replyIncomplete)
+    || !isTeacherReplyEnvelope(raw)) return;
+  const parsed = parseTeacherReply(raw);
+  if (parsed.incomplete) {
+    // Keep the previous text and diagnostics as evidence, but do not present a
+    // legacy half-sentence as a complete reply.
+    request.replyIncomplete = true;
+    return;
+  }
+  const previous = request.response.trim();
+  // The retained raw data must extend or confirm the existing prose. A stale or
+  // unrelated archive must not replace a useful answer with different content.
+  if (previous && !parsed.reply.trim().startsWith(previous)
+    && previous !== '这次回复没有完整解析，请重试。'
+    && previous !== raw.trim() && !request.replyIncomplete) return;
+  request.response = parsed.reply;
+  request.suggestedQuestions = parsed.quickReplies;
+  delete request.replyIncomplete;
+  if (parsed.parseError) request.replyParseError = parsed.parseError;
+  else {
+    delete request.replyParseError;
+    delete request.discussionError;
+  }
+  // Unlike applying a new reply, reading history never discards the original.
+}
+
 export function teacherTopicId(id: string): string {
   if (!/^[0-9a-f]{8}(?:-[0-9a-f]{4}){3}-[0-9a-f]{12}$/i.test(id))
     throw new TeacherError(400, 'teacher_topic_invalid', '智能体话题标识无效。');
@@ -60,16 +91,20 @@ export class TeacherTopicStore {
           throw new TeacherError(409, 'teacher_topic_invalid', '智能体历史无法读取。');
         let recovered = false;
         // Legacy component fields are opaque archives: never validate, revive or delete them.
-        for (const request of topic.requests)
+        for (const request of topic.requests) {
           if (request.status === 'preparing' || request.status === 'running') {
             request.status = 'interrupted';
             request.error = '应用已重启，本次回复中断。';
             recovered = true;
           }
+        }
         if (recovered) {
           topic.revision++;
           await this.save(topic);
         }
+        // Apply display repair after restart recovery is saved, so reading a
+        // mixed topic does not incidentally persist completed-reply repairs.
+        for (const request of topic.requests) repairCompletedReply(request);
         return topic;
       })();
       this.cache.set(id, pending);