feat: 完成P6-P8后端能力与P9路由重构（V1-V2,D1,D3,B1-B2,B4,I1-I4,P9A2-P9A3）

server/prisma/schema.prisma

@@ -136,6 +136,8 @@ model Department {
   reimbursement_forms ReimbursementForm[]
   leave_requests      LeaveRequest[]
   workflow_instances  WorkflowInstance[]
+  budget_pools        BudgetPool[]
+  travel_orders       TravelOrder[]
 
   @@index([parent_id])
   @@map("departments")
@@ -191,6 +193,8 @@ model Employee {
   owned_invoices      InvoicePool[] @relation("InvoiceOwner")
   uploaded_invoices   InvoicePool[] @relation("InvoiceUploader")
   overridden_invoices InvoicePool[] @relation("InvoiceOverrideBy")
+  requested_invoice_verifications InvoiceVerificationRecord[] @relation("InvoiceVerificationRequester")
+  travel_orders                 TravelOrder[]
 
   workflow_instances_started WorkflowInstance[] @relation("WorkflowInstanceSubmitter")
   workflow_history_actions   WorkflowHistory[]  @relation("WorkflowHistoryActor")
@@ -383,6 +387,8 @@ model ReimbursementForm {
   invoice_pool_items InvoicePool[]
   workflow_instances WorkflowInstance[]
   approval_transfers ApprovalTransfer[]
+  budget_ledger_entries BudgetLedgerEntry[]
+  travel_orders         TravelOrder[]
 
   @@index([owner_id])
   @@index([submitter_id])
@@ -514,6 +520,7 @@ model InvoicePool {
   ocr_result           OcrResult?         @relation(fields: [ocr_result_id], references: [id], onDelete: SetNull)
   linked_reimbursement ReimbursementForm? @relation(fields: [linked_reimbursement_id], references: [id], onDelete: SetNull)
   linked_item          ReimbursementItem? @relation(fields: [linked_item_id], references: [id], onDelete: SetNull)
+  verification_records InvoiceVerificationRecord[]
 
   @@index([owner_employee_id])
   @@index([uploaded_by_employee_id])
@@ -526,6 +533,150 @@ model InvoicePool {
   @@map("invoice_pool")
 }
 
+model InvoiceVerificationRecord {
+  id            String   @id @default(uuid()) @db.Uuid
+  invoice_id    String   @db.Uuid
+  provider      String   @db.VarChar(32)
+  status        String   @db.VarChar(16)
+  request_payload Json?
+  result_payload  Json?
+  result_code   String?  @db.VarChar(64)
+  result_message String?
+  error_code    String?  @db.VarChar(64)
+  error_message String?
+  duration_ms   Int?
+  requested_by  String?  @db.Uuid
+  requested_at  DateTime @default(now())
+  completed_at  DateTime?
+  retry_of_id   String?  @db.Uuid
+  attempts      Int      @default(1)
+  created_at    DateTime @default(now())
+  updated_at    DateTime @updatedAt
+
+  invoice   InvoicePool @relation(fields: [invoice_id], references: [id], onDelete: Cascade)
+  requester Employee?   @relation("InvoiceVerificationRequester", fields: [requested_by], references: [id], onDelete: SetNull)
+  retry_of  InvoiceVerificationRecord?  @relation("InvoiceVerificationRetry", fields: [retry_of_id], references: [id], onDelete: SetNull)
+  retries   InvoiceVerificationRecord[] @relation("InvoiceVerificationRetry")
+
+  @@index([invoice_id, created_at], map: "idx_invoice_verification_invoice_created_at")
+  @@index([status, requested_at], map: "idx_invoice_verification_status_requested_at")
+  @@index([requested_by])
+  @@map("invoice_verification_records")
+}
+
+model BudgetPool {
+  id                        String   @id @default(uuid()) @db.Uuid
+  code                      String   @unique
+  name                      String
+  department_id             String?  @db.Uuid
+  status                    String   @default("active") @db.VarChar(16)
+  period_start              DateTime @db.Date
+  period_end                DateTime @db.Date
+  allocated_amount          Decimal  @db.Decimal(14, 2)
+  used_amount               Decimal  @default(0) @db.Decimal(14, 2)
+  warning_threshold_percent Int      @default(80)
+  archived_at               DateTime?
+
+  created_at DateTime @default(now())
+  created_by String?  @db.Uuid
+  updated_at DateTime @updatedAt
+  updated_by String?  @db.Uuid
+
+  department     Department?         @relation(fields: [department_id], references: [id], onDelete: SetNull)
+  ledger_entries BudgetLedgerEntry[]
+
+  @@index([department_id, status], map: "idx_budget_pools_department_status")
+  @@index([status, period_start, period_end], map: "idx_budget_pools_period")
+  @@map("budget_pools")
+}
+
+model BudgetLedgerEntry {
+  id               String   @id @default(uuid()) @db.Uuid
+  budget_pool_id   String   @db.Uuid
+  reimbursement_id String?  @db.Uuid
+  kind             String   @db.VarChar(32)
+  amount           Decimal  @db.Decimal(14, 2)
+  note             String?
+  created_at       DateTime @default(now())
+  created_by       String?  @db.Uuid
+
+  budget_pool        BudgetPool         @relation(fields: [budget_pool_id], references: [id], onDelete: Cascade)
+  reimbursement_form ReimbursementForm? @relation(fields: [reimbursement_id], references: [id], onDelete: SetNull)
+
+  @@index([budget_pool_id, created_at], map: "idx_budget_ledger_pool_created_at")
+  @@index([reimbursement_id])
+  @@map("budget_ledger_entries")
+}
+
+model IntegrationOutbox {
+  id           String   @id @default(uuid()) @db.Uuid
+  event_type   String   @db.VarChar(64)
+  status       String   @default("pending") @db.VarChar(16)
+  payload      Json
+  dedupe_key   String?  @db.VarChar(128)
+  attempts     Int      @default(0)
+  max_attempts Int      @default(5)
+  last_error   String?
+  next_retry_at DateTime?
+  processed_at DateTime?
+  dead_letter_at DateTime?
+
+  created_at DateTime @default(now())
+  created_by String?  @db.Uuid
+  updated_at DateTime @updatedAt
+  updated_by String?  @db.Uuid
+
+  @@unique([event_type, dedupe_key], map: "integration_outbox_event_dedupe_ux")
+  @@index([status, next_retry_at, created_at], map: "idx_integration_outbox_queue")
+  @@map("integration_outbox")
+}
+
+model TravelOrder {
+  id                      String   @id @default(uuid()) @db.Uuid
+  source                  String   @default("manual") @db.VarChar(32)
+  external_order_no       String
+  employee_id             String   @db.Uuid
+  department_id           String?  @db.Uuid
+  linked_reimbursement_id String?  @db.Uuid
+  occurred_at             DateTime? @db.Date
+  amount                  Decimal? @db.Decimal(14, 2)
+  currency                String   @default("CNY") @db.VarChar(8)
+  status                  String   @default("imported") @db.VarChar(20)
+  raw_payload             Json?
+
+  created_at DateTime @default(now())
+  created_by String?  @db.Uuid
+  updated_at DateTime @updatedAt
+  updated_by String?  @db.Uuid
+
+  employee             Employee           @relation(fields: [employee_id], references: [id], onDelete: Restrict)
+  department           Department?        @relation(fields: [department_id], references: [id], onDelete: SetNull)
+  linked_reimbursement ReimbursementForm? @relation(fields: [linked_reimbursement_id], references: [id], onDelete: SetNull)
+
+  @@unique([source, external_order_no], map: "travel_orders_source_order_ux")
+  @@index([employee_id, occurred_at], map: "idx_travel_orders_employee_occurred")
+  @@index([linked_reimbursement_id])
+  @@map("travel_orders")
+}
+
+model NotificationChannel {
+  id           String  @id @default(uuid()) @db.Uuid
+  channel_type String  @db.VarChar(32)
+  name         String
+  enabled      Boolean @default(true)
+  config_json  Json
+  template_json Json?
+
+  created_at DateTime @default(now())
+  created_by String?  @db.Uuid
+  updated_at DateTime @updatedAt
+  updated_by String?  @db.Uuid
+
+  @@unique([channel_type, name], map: "notification_channels_type_name_ux")
+  @@index([enabled, channel_type], map: "idx_notification_channels_enabled_type")
+  @@map("notification_channels")
+}
+
 model WorkflowDefinition {
   id              String  @id @default(uuid()) @db.Uuid
   name            String