feat: 增强差旅报销审核流程与票据智能推理

优化本体解析和编排器的差旅场景处理能力，完善报销单草稿
保存和费用明细同步逻辑，前端报销创建页面增加行程推理和
票据审核交互，新增助手会话快照工具函数，补充单元测试。

web/src/utils/assistantSessionSnapshot.js

@@ -0,0 +1,99 @@
+const SNAPSHOT_VERSION = 1
+const STORAGE_PREFIX = 'x-financial:assistant-session'
+
+export const ASSISTANT_SESSION_SNAPSHOT_EVENT = 'x-financial-assistant-session-snapshot'
+
+function normalizeSessionType(sessionType) {
+  return String(sessionType || 'expense').trim() || 'expense'
+}
+
+function normalizeUserId(userId) {
+  return String(userId || 'anonymous').trim() || 'anonymous'
+}
+
+export function resolveAssistantSessionSnapshotKey(userId, sessionType = 'expense') {
+  return `${STORAGE_PREFIX}:${normalizeUserId(userId)}:${normalizeSessionType(sessionType)}`
+}
+
+function getStorage() {
+  if (typeof window === 'undefined' || !window.localStorage) {
+    return null
+  }
+  return window.localStorage
+}
+
+function emitSnapshotChange(sessionType) {
+  if (typeof window === 'undefined') {
+    return
+  }
+  window.dispatchEvent(new CustomEvent(ASSISTANT_SESSION_SNAPSHOT_EVENT, {
+    detail: { sessionType: normalizeSessionType(sessionType) }
+  }))
+}
+
+export function readAssistantSessionSnapshot(userId, sessionType = 'expense') {
+  const storage = getStorage()
+  if (!storage) {
+    return null
+  }
+
+  try {
+    const rawValue = storage.getItem(resolveAssistantSessionSnapshotKey(userId, sessionType))
+    if (!rawValue) {
+      return null
+    }
+    const parsed = JSON.parse(rawValue)
+    if (!parsed || parsed.version !== SNAPSHOT_VERSION || !parsed.state) {
+      return null
+    }
+    return parsed
+  } catch (error) {
+    console.warn('Failed to read assistant session snapshot:', error)
+    return null
+  }
+}
+
+export function writeAssistantSessionSnapshot(userId, sessionType = 'expense', state = {}) {
+  const storage = getStorage()
+  if (!storage) {
+    return
+  }
+
+  const normalizedSessionType = normalizeSessionType(sessionType)
+  const snapshot = {
+    version: SNAPSHOT_VERSION,
+    updatedAt: Date.now(),
+    userId: normalizeUserId(userId),
+    sessionType: normalizedSessionType,
+    state
+  }
+
+  try {
+    storage.setItem(
+      resolveAssistantSessionSnapshotKey(userId, normalizedSessionType),
+      JSON.stringify(snapshot)
+    )
+    emitSnapshotChange(normalizedSessionType)
+  } catch (error) {
+    console.warn('Failed to write assistant session snapshot:', error)
+  }
+}
+
+export function clearAssistantSessionSnapshot(userId, sessionType = 'expense') {
+  const storage = getStorage()
+  if (!storage) {
+    return
+  }
+
+  const normalizedSessionType = normalizeSessionType(sessionType)
+  try {
+    storage.removeItem(resolveAssistantSessionSnapshotKey(userId, normalizedSessionType))
+    emitSnapshotChange(normalizedSessionType)
+  } catch (error) {
+    console.warn('Failed to clear assistant session snapshot:', error)
+  }
+}
+
+export function hasAssistantSessionSnapshot(userId, sessionType = 'expense') {
+  return Boolean(readAssistantSessionSnapshot(userId, sessionType)?.state)
+}

web/src/utils/reimbursementTextInference.js

@@ -41,6 +41,10 @@ const FLOW_INTENT_KEYWORDS = {
   explain: ['为什么', '依据', '规则', '怎么']
 }
 
+const EXPLICIT_EXPENSE_INTENT_PATTERN = /报销|报账|费用|发票|票据|单据|垫付|报销单|冲销|借款/
+const NON_EXPENSE_INTENT_PATTERN = /怎么部署|如何部署|部署步骤|技术方案|排期|任务|工单|需求|代码|脚本|服务器配置|运维|实施计划|项目计划|会议纪要|周报|日报|总结/
+const BUSINESS_ACTIVITY_PATTERN = /去|到|赴|前往|支撑|支持|部署|实施|驻场|出差|拜访|客户|项目|现场|电力|银行|医院|学校|园区|公司|集团|服务器/
+
 function normalizeCompactText(value) {
   return String(value || '').trim().replace(/\s+/g, '')
 }
@@ -125,11 +129,74 @@ export function inferLocalFlowCandidates(rawText) {
   }
 }
 
+export function shouldRequestExpenseSceneSelection(rawText, options = {}) {
+  if (options.sessionType === DEFAULT_SESSION_TYPE_KNOWLEDGE) {
+    return false
+  }
+  if (Number(options.attachmentCount || 0) > 0) {
+    return false
+  }
+  if (String(options.reviewAction || '').trim()) {
+    return false
+  }
+  if (options.hasSelectedExpenseType) {
+    return false
+  }
+
+  const compact = normalizeCompactText(rawText)
+  if (!compact) {
+    return false
+  }
+  const hasExpenseIntent = /报销|报账|费用|申请/.test(compact)
+  if (!hasExpenseIntent) {
+    return false
+  }
+
+  const candidates = inferLocalFlowCandidates(rawText)
+  return !candidates.expenseType
+}
+
+export function shouldRequestExpenseIntentConfirmation(rawText, options = {}) {
+  if (options.sessionType === DEFAULT_SESSION_TYPE_KNOWLEDGE) {
+    return false
+  }
+  if (Number(options.attachmentCount || 0) > 0) {
+    return false
+  }
+  if (String(options.reviewAction || '').trim()) {
+    return false
+  }
+  if (options.hasConfirmedExpenseIntent || options.hasSelectedExpenseType) {
+    return false
+  }
+
+  const compact = normalizeCompactText(rawText)
+  if (!compact || compact.length < 6) {
+    return false
+  }
+  if (EXPLICIT_EXPENSE_INTENT_PATTERN.test(compact)) {
+    return false
+  }
+  if (NON_EXPENSE_INTENT_PATTERN.test(compact)) {
+    return false
+  }
+
+  return BUSINESS_ACTIVITY_PATTERN.test(compact)
+}
+
 export function buildLocalIntentPreview(rawText, sessionType = DEFAULT_SESSION_TYPE_EXPENSE, options = {}) {
   if (sessionType === DEFAULT_SESSION_TYPE_KNOWLEDGE) {
     return '初步识别为财务知识问答，正在准备检索范围'
   }
 
+  if (shouldRequestExpenseIntentConfirmation(rawText, { ...options, sessionType })) {
+    return '识别到业务事项描述，但是否发起报销尚不明确，需要先由用户确认'
+  }
+
+  if (shouldRequestExpenseSceneSelection(rawText, { ...options, sessionType })) {
+    return '初步识别为报销申请，但报销场景尚未明确，需要先由用户选择场景'
+  }
+
   const compact = normalizeCompactText(rawText)
   const intentLabels = options.intentLabels || DEFAULT_INTENT_LABELS
   const intentKey = Object.entries(FLOW_INTENT_KEYWORDS).find(([, keywords]) =>