Pod quota is silently unlimited in subdomain mode (searchPimStorage bails at root containers) #2209

Environment

• Pivot with CSS 7.2.0
  with a pod quota counter strategy see https://github.com/solid-contrib/pivot/blob/pod-quota-counter/POD-STORAGE-QUOTA.md

Description

• Problem
  With subdomain identifier strategy + pod quota, quota is never enforced:
  PodQuotaStrategy.searchPimStorage tests identifierStrategy.isRootContainer()
  BEFORE reading metadata. In subdomain mode every pod root (e.g.
  https://alice.example.com/) IS a root container, so discovery returns "no
  storage" without checking the pim:Storage metadata. getTotalSpaceUsed
  then returns MAX_SAFE_INTEGER → writes are never limited.

• Repro

  • Run with css:config/util/identifiers/subdomain.json and
    css:config/storage/backend/pod-quota-file.json.
  • Create a pod (subdomain), write beyond the limit → write succeeds (no 413).

• Root cause
  PodQuotaStrategy.searchPimStorage (dist/storage/quota/PodQuotaStrategy.js)
  returns early when isRootContainer(identifier), conflating "no parent
  container above this" with "this container is not a pod". The metadata check
  must come first: a root container CAN be a pod (it has pim:Storage).

• Suggested fix
  Check pim:Storage metadata before the root-container stop, and only fall
  back to "no pod" after the metadata check at a root container:

// read metadata → if hasPimStorage return identifier
// else if isRootContainer return undefined
// else recurse to parent