R47 A1-A8：完成薪资管理模块

server/prisma/schema.prisma

@@ -363,6 +363,16 @@ enum EmployeeTrainingStatus {
   cancelled
 }
 
+enum SalaryItemType {
+  earning
+  deduction
+}
+
+enum PayslipStatus {
+  draft
+  issued
+}
+
 enum PerformanceReviewCycleType {
   monthly
   quarterly
@@ -630,6 +640,8 @@ model Employee {
   contracts                            EmployeeContract[]
   trainings                            EmployeeTraining[]
   certificates                         EmployeeCertificate[]
+  salary_profiles                      EmployeeSalary[]
+  payslips                             Payslip[]
   performance_reviews_received         PerformanceReview[]           @relation("PerformanceReviewEmployee")
   performance_reviews_authored         PerformanceReview[]           @relation("PerformanceReviewReviewer")
 
@@ -2089,6 +2101,84 @@ model EmployeeCertificate {
   @@map("employee_certificates")
 }
 
+model SalaryItem {
+  id         String         @id @default(uuid()) @db.Uuid
+  name       String         @unique
+  item_type  SalaryItemType
+  sort_order Int
+  enabled    Boolean        @default(true)
+
+  created_at DateTime @default(now())
+  created_by String?  @db.Uuid
+  updated_at DateTime @default(now()) @updatedAt
+  updated_by String?  @db.Uuid
+
+  employee_salaries EmployeeSalary[]
+  payslip_items     PayslipItem[]
+
+  @@index([enabled, sort_order], map: "idx_salary_items_enabled_sort")
+  @@map("salary_items")
+}
+
+model EmployeeSalary {
+  id             String   @id @default(uuid()) @db.Uuid
+  employee_id    String   @db.Uuid
+  salary_item_id String   @db.Uuid
+  monthly_amount Decimal  @db.Decimal(12, 2)
+  effective_date DateTime @db.Date
+
+  created_at DateTime @default(now())
+  created_by String?  @db.Uuid
+  updated_at DateTime @default(now()) @updatedAt
+  updated_by String?  @db.Uuid
+
+  employee    Employee   @relation(fields: [employee_id], references: [id], onDelete: Cascade)
+  salary_item SalaryItem @relation(fields: [salary_item_id], references: [id], onDelete: Restrict)
+
+  @@unique([employee_id, salary_item_id, effective_date], map: "employee_salaries_employee_item_effective_ux")
+  @@index([employee_id, effective_date], map: "idx_employee_salaries_employee_effective")
+  @@index([salary_item_id], map: "idx_employee_salaries_salary_item")
+  @@map("employee_salaries")
+}
+
+model Payslip {
+  id               String        @id @default(uuid()) @db.Uuid
+  employee_id      String        @db.Uuid
+  pay_month        DateTime      @db.Date
+  status           PayslipStatus @default(draft)
+  gross_amount     Decimal       @default(0) @db.Decimal(12, 2)
+  deduction_amount Decimal       @default(0) @db.Decimal(12, 2)
+  net_amount       Decimal       @default(0) @db.Decimal(12, 2)
+  issued_at        DateTime?
+
+  created_at DateTime @default(now())
+  created_by String?  @db.Uuid
+  updated_at DateTime @default(now()) @updatedAt
+  updated_by String?  @db.Uuid
+
+  employee Employee      @relation(fields: [employee_id], references: [id], onDelete: Cascade)
+  items    PayslipItem[]
+
+  @@unique([employee_id, pay_month], map: "payslips_employee_month_ux")
+  @@index([pay_month, status], map: "idx_payslips_month_status")
+  @@index([employee_id, pay_month], map: "idx_payslips_employee_month")
+  @@map("payslips")
+}
+
+model PayslipItem {
+  id             String   @id @default(uuid()) @db.Uuid
+  payslip_id     String   @db.Uuid
+  salary_item_id String   @db.Uuid
+  amount         Decimal  @default(0) @db.Decimal(12, 2)
+
+  payslip     Payslip    @relation(fields: [payslip_id], references: [id], onDelete: Cascade)
+  salary_item SalaryItem @relation(fields: [salary_item_id], references: [id], onDelete: Restrict)
+
+  @@unique([payslip_id, salary_item_id], map: "payslip_items_payslip_salary_item_ux")
+  @@index([salary_item_id], map: "idx_payslip_items_salary_item")
+  @@map("payslip_items")
+}
+
 model PerformanceReviewCycle {
   id           String                       @id @default(uuid()) @db.Uuid
   name         String