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/documents/[id]/route.ts

@@ -0,0 +1,44 @@
+import { NextResponse } from "next/server"
+import { and, eq } from "drizzle-orm"
+import { db } from "@/lib/db"
+import { documents } from "@/lib/db/schema"
+import { getSessionUser } from "@/lib/session"
+import { deleteFile } from "@/lib/storage"
+
+export async function GET(_: Request, { params }: { params: Promise<{ id: string }> }) {
+  const user = await getSessionUser()
+  if (!user) return NextResponse.json({ error: "Unauthorized" }, { status: 401 })
+
+  const { id } = await params
+  const doc = await db.query.documents.findFirst({
+    where: and(eq(documents.id, id), eq(documents.user_id, user.id)),
+  })
+
+  if (!doc) return NextResponse.json({ error: "Not found" }, { status: 404 })
+
+  // file_url already points at the auth-gated /api/files route; expose it as
+  // signed_url for compatibility with the existing client.
+  return NextResponse.json({ ...doc, signed_url: doc.file_url })
+}
+
+export async function DELETE(_: Request, { params }: { params: Promise<{ id: string }> }) {
+  const user = await getSessionUser()
+  if (!user) return NextResponse.json({ error: "Unauthorized" }, { status: 401 })
+
+  const { id } = await params
+
+  const doc = await db.query.documents.findFirst({
+    where: and(eq(documents.id, id), eq(documents.user_id, user.id)),
+    columns: { storage_path: true },
+  })
+
+  if (!doc) return NextResponse.json({ error: "Not found" }, { status: 404 })
+
+  await db.delete(documents).where(and(eq(documents.id, id), eq(documents.user_id, user.id)))
+
+  if (doc.storage_path) {
+    await deleteFile(doc.storage_path)
+  }
+
+  return NextResponse.json({ success: true })
+}