feat(pitch-deck): passwordless investor auth, audit logs, snapshots & PWA (#2)

Adds investor-facing access controls, persistence, and PWA support to the pitch deck:

- Passwordless magic-link auth (jose JWT + nodemailer SMTP)
- Per-investor audit logging (logins, slide views, assumption changes, chat)
- Financial model snapshot persistence (auto-save/restore per investor)
- PWA support (manifest, service worker, offline caching, branded icons)
- Safeguards: email watermark overlay, security headers, content protection,
  rate limiting, IP/new-IP detection, single active session per investor
- Admin API: invite, list investors, revoke, query audit logs
- pitch-deck service added to docker-compose.coolify.yml

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

pitch-deck/app/api/auth/logout/route.ts

@@ -0,0 +1,14 @@
+import { NextRequest, NextResponse } from 'next/server'
+import { getSessionFromCookie, revokeSession, clearSessionCookie, logAudit } from '@/lib/auth'
+
+export async function POST(request: NextRequest) {
+  const session = await getSessionFromCookie()
+
+  if (session) {
+    await revokeSession(session.sessionId)
+    await logAudit(session.sub, 'logout', {}, request, undefined, session.sessionId)
+  }
+
+  await clearSessionCookie()
+  return NextResponse.json({ success: true })
+}