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>

app/(dashboard)/calendar/page.tsx

@@ -0,0 +1,52 @@
+import { redirect } from "next/navigation"
+import { and, eq, gte, lte } from "drizzle-orm"
+import { db } from "@/lib/db"
+import { rent_payments, leases } from "@/lib/db/schema"
+import { getSessionUser } from "@/lib/session"
+import { CalendarClient } from "./calendar-client"
+
+export const metadata = { title: "Calendar" }
+
+export default async function CalendarPage() {
+  const user = await getSessionUser()
+  if (!user) redirect("/login")
+
+  const now = new Date()
+  const rangeStart = new Date(now.getFullYear(), now.getMonth() - 1, 1)
+  const rangeEnd = new Date(now.getFullYear(), now.getMonth() + 3, 0)
+
+  const [payments, leaseList] = await Promise.all([
+    db.query.rent_payments.findMany({
+      where: and(
+        eq(rent_payments.user_id, user.id),
+        gte(rent_payments.due_date, rangeStart.toISOString().slice(0, 10)),
+        lte(rent_payments.due_date, rangeEnd.toISOString().slice(0, 10))
+      ),
+      columns: { id: true, due_date: true, amount: true, status: true },
+      with: {
+        tenant: { columns: { first_name: true, last_name: true } },
+      },
+    }),
+    db.query.leases.findMany({
+      where: and(
+        eq(leases.user_id, user.id),
+        gte(leases.lease_end, new Date().toISOString().slice(0, 10))
+      ),
+      columns: { id: true, lease_end: true },
+      with: {
+        tenant: { columns: { first_name: true, last_name: true } },
+        property: { columns: { name: true } },
+      },
+    }),
+  ])
+
+  return (
+    <div className="max-w-5xl mx-auto">
+      <div className="mb-6">
+        <h2 className="text-lg font-bold text-white">Calendar</h2>
+        <p className="text-sm text-white/40 mt-0.5">Rent due dates and lease expirations at a glance</p>
+      </div>
+      <CalendarClient payments={payments ?? []} leases={leaseList ?? []} />
+    </div>
+  )
+}