* Aurral: build the pnpm workspace and run backend/server.ts
v2.12.0 moved from npm workspaces to pnpm and the backend entry to server.ts, so npm ci --workspace frontend found no workspace. Updates point existing units at server.ts.
* Aurral: install only the frontend and backend packages
The workspace root's prepare script runs vp config, which needs git; the upstream image filters the install to the two packages as well.
* Aurral: install git for the workspace prepare script
The root prepare script runs vp config, which aborts when git is missing and only notes the absent .git directory otherwise.