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/team/accept/[token]/page.tsx

@@ -0,0 +1,53 @@
+import Link from "next/link"
+import { redirect } from "next/navigation"
+import { getSessionUser } from "@/lib/session"
+import { acceptInvite } from "@/app/actions/team"
+import { Logo } from "@/components/shared/logo"
+import { XCircle } from "lucide-react"
+
+export const metadata = { title: "Accept Team Invite" }
+
+export default async function AcceptInvitePage({
+  params,
+}: {
+  params: Promise<{ token: string }>
+}) {
+  const { token } = await params
+
+  // Require login. Bounce through /login with a next param so the user lands
+  // back here (and the invite is accepted) after signing in.
+  const user = await getSessionUser()
+  if (!user) {
+    const next = encodeURIComponent(`/team/accept/${token}`)
+    redirect(`/login?next=${next}`)
+  }
+
+  const result = await acceptInvite(token)
+
+  // On success, drop them straight into the dashboard operating under the
+  // owner's account.
+  if (result.ok) redirect("/dashboard")
+
+  return (
+    <div className="flex min-h-screen items-center justify-center bg-[#09090b] px-4">
+      <div className="w-full max-w-md">
+        <div className="mb-8 flex flex-col items-center">
+          <Logo size="lg" />
+        </div>
+        <div className="rounded-xl border border-white/10 bg-[#111118] p-8 text-center">
+          <div className="mx-auto mb-4 w-fit rounded-xl bg-red-500/10 p-3">
+            <XCircle className="h-6 w-6 text-red-400" />
+          </div>
+          <h1 className="text-lg font-semibold text-white">Can&apos;t accept this invite</h1>
+          <p className="mx-auto mt-2 max-w-sm text-sm text-white/50">{result.error}</p>
+          <Link
+            href="/dashboard"
+            className="mt-6 inline-flex items-center justify-center rounded-lg bg-indigo-600 px-5 py-2.5 text-sm font-semibold text-white transition hover:bg-indigo-500"
+          >
+            Go to dashboard
+          </Link>
+        </div>
+      </div>
+    </div>
+  )
+}