feat: build core API, fraud engine, notifier, and frontend

Phase 1 — Core API (Go):
- Events, guests, tokens, RSVPs CRUD on PostgreSQL via pgx/v5
- HMAC-signed per-guest tokens with format validation
- Health endpoint with DB ping, slog JSON logging, graceful shutdown

Phase 2 — NATS + Fraud Engine:
- NATS JetStream pub/sub with explicit-ack consumers
- Python/FastAPI fraud engine with heuristic risk scoring
  (fingerprint mismatch, IP change, missing signals, repeated access)
- gRPC sync scoring with 250ms fail-open timeout
- Per-guest baseline tracking; risk bands low/medium/high/block

Phase 3 — Notifications + Frontend:
- Notification worker scaffolding (Twilio/SES stubs, retry/backoff)
- Nuxt 3 frontend with Tailwind dark theme + brand green
- Live monitor via WebSocket with auto-reconnect
- Activity history endpoint backfills monitor with RSVPs +
  scored access checks (including blocked attempts)

UX polish:
- Marketing-friendly landing page (hero mockup, how-it-works,
  features, use cases, testimonials, FAQ, final CTA)
- Animated layered card mockups on landing + new-event page
- Plus-ones stepper, RSVP status badges, filter buttons
- Friendly access-check labels (Verified/Review/Suspicious/Blocked)
- Dashboard hydration fix via ClientOnly wrapper

Infrastructure:
- docker-compose for full local dev (postgres, nats, api,
  fraud-engine, notifier, frontend)
- Multi-stage Dockerfiles, non-root UID 1000
- Integration tests with testcontainers-go

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

frontend/nuxt.config.ts

@@ -0,0 +1,25 @@
+// https://nuxt.com/docs/api/configuration/nuxt-config
+export default defineNuxtConfig({
+  compatibilityDate: '2024-09-01',
+  devtools: { enabled: false },
+  modules: ['@nuxtjs/tailwindcss'],
+  css: ['~/assets/css/main.css'],
+  app: {
+    head: {
+      title: 'GuestGuard',
+      meta: [
+        { charset: 'utf-8' },
+        { name: 'viewport', content: 'width=device-width, initial-scale=1' },
+        { name: 'description', content: 'Real-time fraud detection for event RSVPs.' },
+      ],
+    },
+  },
+  runtimeConfig: {
+    public: {
+      // For local dev across origins. In prod this should be empty so all
+      // requests go through same-origin via an ingress proxy.
+      apiBase: process.env.NUXT_PUBLIC_API_BASE || 'http://localhost:8080',
+      wsBase: process.env.NUXT_PUBLIC_WS_BASE || 'ws://localhost:8080',
+    },
+  },
+})