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/api/export/tenants/route.ts

@@ -0,0 +1,44 @@
+import { NextResponse } from "next/server"
+import { asc, eq } from "drizzle-orm"
+import { db } from "@/lib/db"
+import { tenants } from "@/lib/db/schema"
+import { getSessionUser } from "@/lib/session"
+
+export async function GET() {
+  const user = await getSessionUser()
+  if (!user) return NextResponse.json({ error: "Unauthorized" }, { status: 401 })
+
+  const rows = await db.query.tenants.findMany({
+    where: eq(tenants.user_id, user.id),
+    with: {
+      property: { columns: { name: true } },
+      unit: { columns: { unit_number: true } },
+    },
+    orderBy: asc(tenants.last_name),
+  })
+
+  const headers = ["First Name", "Last Name", "Email", "Phone", "Property", "Unit", "Status", "Move In Date", "Notes"]
+  const lines = [
+    headers.join(","),
+    ...rows.map((t) => [
+      `"${t.first_name ?? ""}"`,
+      `"${t.last_name ?? ""}"`,
+      `"${t.email ?? ""}"`,
+      `"${t.phone ?? ""}"`,
+      `"${t.property?.name ?? ""}"`,
+      `"${t.unit?.unit_number ?? ""}"`,
+      t.status ?? "",
+      t.move_in_date ?? "",
+      `"${(t.notes ?? "").replace(/"/g, "'")}"`,
+    ].join(","))
+  ]
+
+  const csv = lines.join("\n")
+
+  return new NextResponse(csv, {
+    headers: {
+      "Content-Type": "text/csv; charset=utf-8",
+      "Content-Disposition": 'attachment; filename="tenants.csv"',
+    },
+  })
+}