Initial import: property management SaaS + security hardening + admin dashboard

Property Management Network — Next.js 16 (App Router), Better Auth,
Drizzle ORM over PostgreSQL, Stripe, OpenAI, Resend.

Includes:
- Security hardening: access-control/IDOR fixes, TLS-by-default DB layer,
  constant-time cron auth, strict security headers, atomic AI quota gating,
  HTML/email output encoding, demo-backdoor disabled in production.
- Superadmin dashboard at /admin (overview/MRR, server-paginated users with
  ban/impersonate/plan/delete, billing, platform activity + admin audit log,
  AI usage, system health) via the Better Auth admin plugin.
- Seed/migration utility scripts under scripts/.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

.env.example

@@ -0,0 +1,48 @@
+# ============================================
+# PROPERTY MANAGEMENT NETWORK — Environment Variables
+# ============================================
+# Copy this file to .env.local and fill in your values.
+# Never commit .env.local to version control.
+
+# === DATABASE (external Postgres) ===
+# Standard Postgres connection string.
+DATABASE_URL=postgres://user:password@host:5432/dbname
+
+# === BETTER AUTH ===
+# Generate a secret: node -e "console.log(require('crypto').randomBytes(32).toString('hex'))"
+BETTER_AUTH_SECRET=your-random-secret-here
+BETTER_AUTH_URL=http://localhost:3000
+
+# Google OAuth — create credentials at https://console.cloud.google.com
+# Authorized redirect URI: <BETTER_AUTH_URL>/api/auth/callback/google
+GOOGLE_CLIENT_ID=
+GOOGLE_CLIENT_SECRET=
+
+# === STORAGE (local disk) ===
+# Directory where uploaded files are stored (kept out of the public web root).
+STORAGE_DIR=./storage
+
+# === STRIPE ===
+# Get from: https://dashboard.stripe.com/apikeys
+STRIPE_SECRET_KEY=sk_test_your-secret-key
+STRIPE_WEBHOOK_SECRET=whsec_your-webhook-secret
+NEXT_PUBLIC_STRIPE_PUBLISHABLE_KEY=pk_test_your-publishable-key
+
+# Stripe Price IDs — create in Stripe Dashboard > Products
+STRIPE_PRO_MONTHLY_PRICE_ID=price_your-pro-monthly-id
+STRIPE_LANDLORD_MONTHLY_PRICE_ID=price_your-landlord-monthly-id
+STRIPE_LIFETIME_PRICE_ID=price_your-lifetime-id
+
+# === AI (OpenAI) ===
+# Get from: https://platform.openai.com/api-keys
+OPENAI_API_KEY=sk-your-api-key
+
+# === EMAIL (Resend) ===
+# Get from: https://resend.com/api-keys
+RESEND_API_KEY=re_your-api-key
+RESEND_FROM_EMAIL=noreply@yourdomain.com
+
+# === APP ===
+NEXT_PUBLIC_APP_URL=http://localhost:3000
+NEXT_PUBLIC_APP_NAME=Property Management Network
+CRON_SECRET=your-random-secret-string