feat: add monitoring dashboard (Prometheus + Grafana + Umami + Admin)

Phase 1: Infrastructure
- Add docker/prometheus/prometheus.yml with scrape configs for all services
- Add docker/grafana/provisioning for auto-configured datasources
- Add docker/grafana/dashboards (system-overview, backends-docker)
- Update docker-compose.macmini.yml with monitoring services:
  - prometheus, grafana, node-exporter, cadvisor
  - postgres-exporter, redis-exporter, umami
- Add grafana.mana.how and analytics.mana.how to Caddyfile

Phase 2: Backend Metrics
- Create packages/shared-nestjs-metrics with:
  - MetricsModule (auto /metrics endpoint)
  - MetricsService (Counter, Histogram, Gauge helpers)
  - MetricsMiddleware (auto HTTP request tracking)

Phase 3: Umami Web Analytics
- Add Umami tracking scripts to all landing pages
- Add Umami tracking scripts to all web apps
- Create scripts/mac-mini/setup-umami-db.sh

Phase 4: Admin Dashboard (ManaCore Web)
- Add admin routes: /admin, /admin/users, /admin/system
- Create StatCard, QuickLinks, UserTable components
- Add Admin link to navigation

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

scripts/mac-mini/setup-umami-db.sh

@@ -0,0 +1,27 @@
+#!/bin/bash
+# Setup Umami database on Mac Mini
+# Run this script after starting PostgreSQL container
+
+set -e
+
+echo "Creating Umami database..."
+
+# Check if running inside docker network or from host
+if docker ps | grep -q manacore-postgres; then
+    docker exec -i manacore-postgres psql -U postgres <<EOF
+SELECT 'CREATE DATABASE umami' WHERE NOT EXISTS (SELECT FROM pg_database WHERE datname = 'umami')\gexec
+EOF
+    echo "Umami database created successfully!"
+else
+    echo "Error: PostgreSQL container 'manacore-postgres' is not running"
+    echo "Please start it with: docker compose -f docker-compose.macmini.yml up -d postgres"
+    exit 1
+fi
+
+echo ""
+echo "Next steps:"
+echo "1. Start Umami: docker compose -f docker-compose.macmini.yml up -d umami"
+echo "2. Access Umami at: https://analytics.mana.how"
+echo "3. Default login: admin / umami"
+echo "4. Change the password immediately!"
+echo "5. Create websites and get tracking IDs for your apps"