fix: make checkout gates environment-aware

.npmrc

@@ -1,5 +1,5 @@
 @mosaicstack:registry=https://git.mosaicstack.dev/api/packages/mosaicstack/npm/
-# Pin the pnpm store to the same path the ci-base image warms (Dockerfile.ci),
-# so the pipeline `pnpm install --prefer-offline` consumes the baked store
-# instead of repopulating a fresh one.
-store-dir=/root/.local/share/pnpm/store
+# HOME resolves to /root in the ci-base image, preserving its warmed-store path.
+# Non-root checkouts use their own HOME. Override without editing this file via
+# NPM_CONFIG_STORE_DIR (pnpm's environment form of the store-dir setting).
+store-dir=${HOME}/.local/share/pnpm/store