v2.0.0: Complete rewrite — React + Express + PostgreSQL + Docker

BREAKING: Full rewrite from static HTML to production-grade stack.

Features:
- React 18 + Vite + Tailwind CSS (mobile-first)
- Express + Prisma + PostgreSQL backend
- JWT authentication with role-based access
- Weekly Mon-Sun timesheets with auto-save
- Multiple homeowner entries per day
- Submit → Approve/Reject workflow
- Server-side PDF generation
- SMTP email integration
- Admin panel with reporting & filters
- Dark mode (system-aware)
- Docker Compose one-command deploy
- Non-root containers, Helmet, bcrypt, Zod validation

backend/prisma/schema.prisma

@@ -0,0 +1,106 @@
+generator client {
+  provider = "prisma-client-js"
+}
+
+datasource db {
+  provider = "postgresql"
+  url      = env("DATABASE_URL")
+}
+
+enum Role {
+  employee
+  admin
+  super_admin
+}
+
+enum TimesheetStatus {
+  draft
+  submitted
+  approved
+  rejected
+}
+
+model User {
+  id            String    @id @default(uuid())
+  email         String    @unique
+  name          String
+  role          Role      @default(employee)
+  passwordHash  String    @map("password_hash")
+  isActive      Boolean   @default(true) @map("is_active")
+  refreshToken  String?   @map("refresh_token")
+  createdAt     DateTime  @default(now()) @map("created_at")
+  updatedAt     DateTime  @updatedAt @map("updated_at")
+
+  timeEntries   TimeEntry[]
+  timesheets    Timesheet[]        @relation("UserTimesheets")
+  approvals     Timesheet[]        @relation("ApprovedTimesheets")
+
+  @@map("users")
+}
+
+model Homeowner {
+  id        String    @id @default(uuid())
+  name      String    @unique
+  address   String?
+  isActive  Boolean   @default(true) @map("is_active")
+  createdAt DateTime  @default(now()) @map("created_at")
+  updatedAt DateTime  @updatedAt @map("updated_at")
+
+  timeEntries TimeEntry[]
+
+  @@map("homeowners")
+}
+
+model TimeEntry {
+  id              String    @id @default(uuid())
+  userId          String    @map("user_id")
+  date            DateTime  @db.Date
+  homeownerId     String    @map("homeowner_id")
+  hoursWorked     Decimal   @map("hours_worked") @db.Decimal(4, 2)
+  workDescription String    @map("work_description")
+  createdAt       DateTime  @default(now()) @map("created_at")
+  updatedAt       DateTime  @updatedAt @map("updated_at")
+
+  user            User      @relation(fields: [userId], references: [id], onDelete: Cascade)
+  homeowner       Homeowner @relation(fields: [homeownerId], references: [id])
+  timesheetLinks  TimesheetEntry[]
+
+  @@index([userId, date])
+  @@index([homeownerId])
+  @@map("time_entries")
+}
+
+model Timesheet {
+  id          String          @id @default(uuid())
+  userId      String          @map("user_id")
+  weekStart   DateTime        @map("week_start") @db.Date
+  weekEnd     DateTime        @map("week_end") @db.Date
+  status      TimesheetStatus @default(draft)
+  submittedAt DateTime?       @map("submitted_at")
+  approvedBy  String?         @map("approved_by")
+  approvedAt  DateTime?       @map("approved_at")
+  notes       String?
+  createdAt   DateTime        @default(now()) @map("created_at")
+  updatedAt   DateTime        @updatedAt @map("updated_at")
+
+  user        User            @relation("UserTimesheets", fields: [userId], references: [id], onDelete: Cascade)
+  approver    User?           @relation("ApprovedTimesheets", fields: [approvedBy], references: [id])
+  entries     TimesheetEntry[]
+
+  @@unique([userId, weekStart])
+  @@index([status])
+  @@index([userId, weekStart])
+  @@map("timesheets")
+}
+
+model TimesheetEntry {
+  id          String    @id @default(uuid())
+  timesheetId String    @map("timesheet_id")
+  timeEntryId String    @map("time_entry_id")
+
+  timesheet   Timesheet @relation(fields: [timesheetId], references: [id], onDelete: Cascade)
+  timeEntry   TimeEntry @relation(fields: [timeEntryId], references: [id], onDelete: Cascade)
+
+  @@unique([timesheetId, timeEntryId])
+  @@map("timesheet_entries")
+}