The deploy host only has Docker installed, not Node/npm directly, so the
original `npm install` / `node hash-password.js` steps failed with
"command not found". Both the bcrypt hash and session secret are now
generated with a throwaway `node:22-alpine` container instead.
Adds a self-service editor at admin.larpaso.de so texts, images, links,
Impressum/Datenschutz, fonts, font sizes and colors can be changed without
a developer. All homepage/legal content moves into content/site.json and
a new content/theme.json drives every CSS color/font/size token; the
Astro pages read from these at build time.
The admin/ service (Node/Express) provides bcrypt+session login with
rate limiting, a schema-driven form UI (including a hex/RGB/alpha color
picker), image upload, and a publish action that runs the Astro build
and republishes into a volume shared with the nginx website container -
so edits go live without redeploying that container.
See DEPLOYMENT_ADMIN.md for the server-side setup steps.
