feat: monorepo with NestJS API, admin panel and DB-driven website

Restructure the repo into a pnpm + Turborepo monorepo:

- apps/web: Nuxt 4 site, now server-rendered and reading all content
  from the API; pages cached with SWR and purged on content changes
- apps/api: NestJS 12 + Prisma 7 + PostgreSQL. Auth with short-lived
  access tokens and rotating httpOnly refresh cookies, roles (ADMIN,
  EDITOR), catalog, editable site sections, media upload to S3-compatible
  storage (converted to WebP), contact messages, audit log
- apps/admin: Vue 3 admin panel (Ant Design Vue, Pinia, Tailwind) for
  products, categories, site sections, messages, media and users
- packages/shared: Zod schemas and types shared by API and admin

Also:
- seed script that loads the original 8 categories / 89 products and
  section content
- Docker images for api (with a one-off migrate service), web, admin,
  and an nginx gateway for both domains
- dev and production compose files, daily database backup service
- API e2e tests

Removes the committed static out/ build and the old root Dockerfile.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.env.example

@@ -0,0 +1,34 @@
+# Production settings for docker-compose.yml — copy to .env and change every secret.
+# Generate secrets with: node -e "console.log(require('crypto').randomBytes(48).toString('base64url'))"
+
+# domains (TLS is terminated in front of the gateway: host nginx, Traefik or the CDN)
+SITE_DOMAIN=imenpishgaman.ir
+ADMIN_DOMAIN=admin.imenpishgaman.ir
+# host port of the gateway container
+HTTP_PORT=8080
+# reverse proxies in front of the API: gateway (1) + host TLS proxy (1)
+TRUST_PROXY=2
+# set to false only if the admin is served over plain http
+COOKIE_SECURE=true
+
+# database
+POSTGRES_USER=imen
+POSTGRES_PASSWORD=change-me
+POSTGRES_DB=imen
+
+# object storage (MinIO container); bucket is created automatically
+S3_BUCKET=imen-media
+S3_ACCESS_KEY=imen
+S3_SECRET_KEY=change-me-at-least-8-chars
+
+# auth + cache purge secrets
+JWT_SECRET=change-me-48-random-bytes
+REVALIDATE_SECRET=change-me-too
+
+# first admin user (created by: docker compose exec api node dist/seed/seed.js)
+ADMIN_EMAIL=admin@imenpishgaman.ir
+ADMIN_PASSWORD=change-me
+ADMIN_NAME=مدیر سایت
+
+# npm registry used while building the images (set a mirror if npmjs.org is slow or blocked)
+NPM_REGISTRY=https://registry.npmjs.org/