fix(audit): slim persisted audit results to stop carrying full knowledge base

- drop unused allScoredRecords/groups from audit results
- add slimAuditRecord/toPersistedAuditResult to strip derived fields
  (mdContent/searchText) before attaching results to messages
- sanitize legacy messages when loading conversations so stored
  oversized results are replaced on next save

src/features/audit/engine.js

@@ -329,15 +329,6 @@ export function buildAuditResultFromAnalysis(
     );
   }
   const selectedIdsAfterRules = new Set(selected.map(getAuditRecordKey));
-  const analyzedRecords = records.map((record) => ({
-    ...record,
-    aiSelected: selectedIds.has(getAuditRecordKey(record)),
-    aiExcluded: !selectedIdsAfterRules.has(getAuditRecordKey(record)),
-    skillExcluded:
-      selectedIds.has(getAuditRecordKey(record)) &&
-      !selectedIdsAfterRules.has(getAuditRecordKey(record)),
-    aiRationale: rationale.get(getAuditRecordKey(record)) || '',
-  }));
   return {
     version: 2,
     kind: classifyAuditIntent(isRefine ? baseQuery : query),
@@ -352,11 +343,9 @@ export function buildAuditResultFromAnalysis(
     ),
     threshold: instruction.threshold,
     totalCount: records.length,
-    scoredCount: analyzedRecords.length,
+    scoredCount: records.length,
     matchedCount: selected.length,
     records: selected,
-    allScoredRecords: analyzedRecords,
-    groups: groupAuditRecords(selected),
     generatedAt: new Date().toISOString(),
     selectedRiskPointIds: Array.from(selectedIdsAfterRules),
     reportStyle: skillContext.styles,
@@ -932,13 +921,53 @@ export function buildAuditResult(
     scoredCount: allScored.length,
     matchedCount: selected.length,
     records: selected,
-    allScoredRecords: allScored,
-    groups: groupAuditRecords(selected),
     generatedAt: new Date().toISOString(),
     reportStyle: skillContext.styles,
   };
 }
 
+// 审计结果会挂在消息上随会话记录反复持久化，只保留展示、导出和再调整所需字段；
+// 不携带全量知识库（allScoredRecords/groups）和 mdContent/searchText 等派生大字段。
+const PERSISTED_AUDIT_RECORD_FIELDS = [
+  'id',
+  'riskPointCode',
+  'sheetName',
+  'sourceRow',
+  'sourceFileName',
+  'sourceBatch',
+  'businessSegment',
+  'level1Project',
+  'level2Project',
+  'riskDescription',
+  'regulationBasis',
+  'riskSource',
+  'riskLevel',
+  'remark',
+  'matchScore',
+  'matchLevel',
+  'matchReasons',
+  'aiRationale',
+];
+
+export function slimAuditRecord(record) {
+  if (!record) return record;
+  const slim = {};
+  PERSISTED_AUDIT_RECORD_FIELDS.forEach((key) => {
+    const value = record[key];
+    if (value !== undefined && value !== '') slim[key] = value;
+  });
+  return slim;
+}
+
+export function toPersistedAuditResult(result) {
+  if (!result) return result;
+  const persisted = { ...result };
+  delete persisted.allScoredRecords;
+  delete persisted.groups;
+  persisted.records = (persisted.records || []).map(slimAuditRecord);
+  return persisted;
+}
+
 export function findPreviousAuditResult(messages = []) {
   for (let index = messages.length - 1; index >= 0; index -= 1) {
     if (messages[index]?.auditResult) return messages[index].auditResult;

src/pages/Chat/index.jsx

@@ -42,6 +42,8 @@ import {
   isAuditRefineRequest,
   isPersistentAuditRuleRequest,
   recordMatchesTerms,
+  slimAuditRecord,
+  toPersistedAuditResult,
 } from '../../features/audit/engine';
 import { parseAuditExcelFromRemote } from '../../features/audit/excel';
 import {
@@ -266,6 +268,22 @@ async function readLlmText(response) {
   return content;
 }
 
+// 旧会话可能保存过未瘦身的大体积审计结果，加载时统一裁剪，
+// 避免后续每次保存会话都继续携带全量知识库副本。
+function sanitizePersistedMessage(message) {
+  if (!message?.auditResult && !message?.auditExport) return message;
+  return {
+    ...message,
+    auditResult: toPersistedAuditResult(message.auditResult),
+    auditExport: message.auditExport
+      ? {
+          ...message.auditExport,
+          records: (message.auditExport.records || []).map(slimAuditRecord),
+        }
+      : message.auditExport,
+  };
+}
+
 async function expandAuditQuery(query, model, signal) {
   const response = await llmChat(
     {
@@ -1273,7 +1291,7 @@ export default forwardRef((props, ref) => {
           styleAdjusted: true,
           generatedAt: new Date().toISOString(),
         };
-        pendingAuditResultRef.current = styledResult;
+        pendingAuditResultRef.current = toPersistedAuditResult(styledResult);
         auditKnowledgePrompt = buildAuditStylePrompt(
           styleRequest.changes,
           persisted,
@@ -1365,8 +1383,8 @@ export default forwardRef((props, ref) => {
               console.warn('审计 Skill 业务过滤规则保存失败：', error);
             }
           }
-          pendingAuditResultRef.current = result;
           auditKnowledgePrompt = buildAuditKnowledgePrompt(result);
+          pendingAuditResultRef.current = toPersistedAuditResult(result);
         } else {
           let result = null;
           try {
@@ -1406,7 +1424,7 @@ export default forwardRef((props, ref) => {
           pendingAuditExportRef.current = {
             question: message.content,
             title: '审计知识库问答',
-            records: result.records || [],
+            records: (result.records || []).map(slimAuditRecord),
           };
           auditKnowledgePrompt = buildGroundedAuditKnowledgePrompt(
             result.records || [],
@@ -1701,7 +1719,7 @@ export default forwardRef((props, ref) => {
     setMessages(
       messages.map((message) => ({
         status: 'success',
-        message: message,
+        message: sanitizePersistedMessage(message),
       })),
     );
   }, [conversation]);