fix: copy pnpm-workspace.yaml in prebuilt-debian Dockerfile

pnpm v11 reads allowBuilds from pnpm-workspace.yaml, not package.json.
Without it, better-sqlite3 build scripts are rejected.

deployments/prebuilt-debian/Dockerfile

@@ -2,5 +2,6 @@ FROM node:24.16.0-trixie AS base
 WORKDIR /app
 COPY package.json .
 COPY pnpm-lock.yaml .
+COPY pnpm-workspace.yaml .
 RUN corepack enable pnpm && pnpm install --frozen-lockfile
 CMD ["sleep", "60s"]