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>

internal/domain/event.go

@@ -0,0 +1,44 @@
+package domain
+
+import (
+	"errors"
+	"time"
+
+	"github.com/google/uuid"
+)
+
+type EventStatus string
+
+const (
+	EventStatusDraft     EventStatus = "draft"
+	EventStatusPublished EventStatus = "published"
+	EventStatusClosed    EventStatus = "closed"
+	EventStatusArchived  EventStatus = "archived"
+)
+
+func (s EventStatus) Valid() bool {
+	switch s {
+	case EventStatusDraft, EventStatusPublished, EventStatusClosed, EventStatusArchived:
+		return true
+	}
+	return false
+}
+
+type Event struct {
+	ID          uuid.UUID      `json:"id"`
+	HostID      uuid.UUID      `json:"host_id"`
+	Name        string         `json:"name"`
+	Slug        string         `json:"slug"`
+	EventDate   time.Time      `json:"event_date"`
+	Venue       string         `json:"venue"`
+	MaxCapacity int            `json:"max_capacity"`
+	Settings    map[string]any `json:"settings"`
+	Status      EventStatus    `json:"status"`
+	CreatedAt   time.Time      `json:"created_at"`
+	UpdatedAt   time.Time      `json:"updated_at"`
+}
+
+var (
+	ErrEventNotFound = errors.New("event not found")
+	ErrSlugTaken     = errors.New("slug already in use")
+)