addition expense claims

backend/prisma/schema.prisma

@@ -200,6 +200,7 @@ model Employee {
   commissions       Commission[]
   loans             Loan[]
   purchaseRequests  PurchaseRequest[]
+  expenseClaims     ExpenseClaim[]
   leaveEntitlements LeaveEntitlement[]
   employeeContracts EmployeeContract[]
   tenderDirectivesAssigned TenderDirective[]
@@ -503,6 +504,34 @@ model PurchaseRequest {
   @@map("purchase_requests")
 }
 
+model ExpenseClaim {
+  id              String    @id @default(uuid())
+  employeeId      String
+  employee        Employee  @relation(fields: [employeeId], references: [id])
+
+  claimNumber     String    @unique
+
+  items           Json?
+  totalAmount     Decimal?  @db.Decimal(12, 2)
+
+  expenseDate     DateTime? @db.Date
+  amount          Decimal?  @db.Decimal(12, 2)
+  description     String?
+  projectOrTender String?
+
+  status          String    @default("PENDING")
+  approvedBy      String?
+  approvedAt      DateTime?
+  rejectedReason  String?
+
+  createdAt       DateTime  @default(now())
+  updatedAt       DateTime  @updatedAt
+
+  @@index([employeeId])
+  @@index([status])
+  @@map("expense_claims")
+}
+
 model LeaveEntitlement {
   id            String   @id @default(uuid())
   employeeId    String