docker-mailserver LXC für Proxmox: Stack + Admin-UI + Webmail + Hardening

- dms-lxc.sh: Proxmox-Host-Installer (unprivilegierter LXC, Debian 13, Docker),
  curl-Self-Download, Multi-Domain-DKIM, SnappyMail-Provisionierung, PVE-Firewall
- Stack: docker-mailserver, Node-Admin-API (Supabase-Auth), React-Admin-UI
  (OPENBUREAU-Look), SnappyMail (Shibui-Theme), Rspamd-Web-UI, docker-socket-proxy
- Admin: Postfächer/Aliase/Catch-all/Quota, editierbare Domains+Settings,
  Server (Quota/Queue über abgesicherte Bridge), Status & DNS
- Hardening: no-new-privileges, Whitelisted exec-Bridge, Rspamd-Passwort,
  .env chmod 600, PVE-CT-Firewall, generisch/teilbar (keine festen Domains)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

stack/admin/Dockerfile

@@ -0,0 +1,16 @@
+# ---- Build-Stage: React-Admin mit Vite bauen ----
+FROM node:20-alpine AS build
+WORKDIR /app
+COPY package.json ./
+RUN npm install
+COPY . .
+RUN npm run build
+
+# ---- Serve-Stage: nginx ----
+FROM nginx:alpine
+COPY nginx.conf /etc/nginx/conf.d/default.conf
+COPY --from=build /app/dist /usr/share/nginx/html
+# Laufzeit-Config-Generator (nginx-Image führt /docker-entrypoint.d/*.sh aus)
+COPY docker-entrypoint.d/40-config.sh /docker-entrypoint.d/40-config.sh
+RUN chmod +x /docker-entrypoint.d/40-config.sh
+EXPOSE 80