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/ai/rent-receipt/route.ts

@@ -0,0 +1,61 @@
+import { NextResponse } from "next/server"
+import { z } from "zod"
+import { getSessionUser } from "@/lib/session"
+import { openai } from "@/lib/ai/client"
+import { RENT_RECEIPT_PROMPT, dataBlock } from "@/lib/ai/prompts"
+import { enforceAiQuota } from "@/lib/ai/usage"
+
+// Whitelist only the fields the receipt needs. Never pass the raw request body
+// into the prompt — tenant-controlled strings must not become instructions.
+const ReceiptInput = z.object({
+  payment_id: z.string().optional(),
+  amount: z.number().optional(),
+  tenant_name: z.string().max(200).optional(),
+  property_name: z.string().max(200).optional(),
+  property_address: z.string().max(300).optional(),
+  unit_number: z.string().max(50).optional(),
+  landlord_name: z.string().max(200).optional(),
+  payment_method: z.string().max(100).optional(),
+  due_date: z.string().max(50).optional(),
+  paid_date: z.string().max(50).optional(),
+  period: z.string().max(100).optional(),
+})
+
+export async function POST(request: Request) {
+  const user = await getSessionUser()
+  if (!user) return NextResponse.json({ error: "Unauthorized" }, { status: 401 })
+
+  const quota = await enforceAiQuota(user.id, "ai_rent_receipt")
+  if (!quota.ok) return NextResponse.json({ error: quota.error }, { status: quota.status })
+
+  const parsed = ReceiptInput.safeParse(await request.json())
+  if (!parsed.success) {
+    return NextResponse.json({ error: "Invalid payment details" }, { status: 400 })
+  }
+
+  // Pass only the whitelisted, validated fields to the model.
+  const { payment_id, ...receiptFields } = parsed.data
+
+  const completion = await openai.chat.completions.create({
+    model: "gpt-4o-mini",
+    max_tokens: 1024,
+    messages: [
+      { role: "system", content: RENT_RECEIPT_PROMPT },
+      {
+        role: "user",
+        content: dataBlock("PAYMENT DETAILS", JSON.stringify(receiptFields, null, 2)),
+      },
+    ],
+  })
+
+  const text = completion.choices[0].message.content ?? ""
+
+  let receipt
+  try {
+    receipt = JSON.parse(text.replace(/```json\n?/g, "").replace(/```\n?/g, "").trim())
+  } catch {
+    return NextResponse.json({ error: "Failed to parse AI response" }, { status: 500 })
+  }
+
+  return NextResponse.json(receipt)
+}