Consolidate audit-fixes branch: webhooks, integrations, and deploy hardening

Batch commit of the pending working tree on security/audit-fixes-2026-07.
Major areas:
- Outbound webhooks / Zapier: schema + signed delivery with retries, public
  v1 API (REST-hook subscribe/unsubscribe), settings UI, cron drain.
- Deploy hardening: email via SMTP2GO (Resend fully removed), verified DB TLS
  (DATABASE_SSL=require + DATABASE_CA), storage fails loud in production when
  Spaces is unconfigured instead of silently using ephemeral disk.
- Integrations & features (concurrent work): accounting (QuickBooks/Xero),
  e-signature (DocuSign/Dropbox Sign), PayPal, geocoding/maps, onboarding,
  expanded legal pages.
- DB migrations 0006–0009.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

app/api/maintenance/route.ts

@@ -6,6 +6,8 @@ import { getSessionUser } from "@/lib/session"
 import { maintenanceSchema } from "@/lib/validations"
 import { ownsProperty, ownsUnit, ownsTenant } from "@/lib/db/ownership"
 import { logActivity } from "@/lib/activity"
+import { getEffectiveOwnerId, getAccountContext } from "@/lib/account"
+import { emitWebhookEvent } from "@/lib/webhooks/emit"
 
 const VALID_STATUSES = ["open", "in_progress", "resolved", "closed"]
 const VALID_PRIORITIES = ["low", "medium", "high", "emergency"]
@@ -14,6 +16,8 @@ export async function GET(request: Request) {
   const user = await getSessionUser()
   if (!user) return NextResponse.json({ error: "Unauthorized" }, { status: 401 })
 
+  const ownerId = await getEffectiveOwnerId(user.id)
+
   const { searchParams } = new URL(request.url)
   const status = searchParams.get("status")
   const priority = searchParams.get("priority")
@@ -29,7 +33,7 @@ export async function GET(request: Request) {
 
   const data = await db.query.maintenance_requests.findMany({
     where: and(
-      eq(maintenance_requests.user_id, user.id),
+      eq(maintenance_requests.user_id, ownerId),
       status ? eq(maintenance_requests.status, status as typeof maintenance_requests.$inferSelect.status) : undefined,
       priority ? eq(maintenance_requests.priority, priority as typeof maintenance_requests.$inferSelect.priority) : undefined,
       propertyId ? eq(maintenance_requests.property_id, propertyId) : undefined
@@ -53,8 +57,10 @@ export async function POST(request: Request) {
   let userId: string
 
   if (user) {
-    // Authenticated landlord
-    userId = user.id
+    // Authenticated landlord — scope to the account owner and enforce write access.
+    const ctx = await getAccountContext(user.id)
+    if (!ctx.canWrite) return NextResponse.json({ error: "Forbidden" }, { status: 403 })
+    userId = ctx.ownerId
   } else {
     // Tenant portal submission — verify portal_token
     const portalToken = body.portal_token as string | undefined
@@ -90,9 +96,9 @@ export async function POST(request: Request) {
   // (The portal-token path already validates these against the tenant above.)
   if (
     user &&
-    (!(await ownsProperty(user.id, parsed.data.property_id)) ||
-      !(await ownsUnit(user.id, parsed.data.unit_id)) ||
-      !(await ownsTenant(user.id, parsed.data.tenant_id)))
+    (!(await ownsProperty(userId, parsed.data.property_id)) ||
+      !(await ownsUnit(userId, parsed.data.unit_id)) ||
+      !(await ownsTenant(userId, parsed.data.tenant_id)))
   ) {
     return NextResponse.json({ error: "Forbidden" }, { status: 403 })
   }
@@ -111,5 +117,11 @@ export async function POST(request: Request) {
     entityId: data.id,
   })
 
+  await emitWebhookEvent({
+    ownerId: userId,
+    event: "maintenance.created",
+    data: { maintenance: data },
+  })
+
   return NextResponse.json(data, { status: 201 })
 }