(1.37) Add "Pod shared pool" to glossary

**This is a feature request**

**Problem:** The [preview](https://deploy-preview-55932--kubernetes-io-vnext-staging.netlify.app/docs/concepts/resource-management/pod-level-resource-managers/#glossary) of the Kubernetes **v1.37** docs for _Pod level resource managers_ includes a page-level glossary, with entries for:

- Pod level resources specification
- Guaranteed container
- Exclusive slice
- Pod shared pool

These definitions are only mentioned on that page.

**Proposed Solution:**

This issue proposes adding "Pod shared pool" to the main [glossary](https://kubernetes.io/docs/reference/glossary/).

**Additional Information:**
/help
/language en
/priority backlog

If v1.37 has been released, the change to make will be against the _main_ branch; otherwise, it will be against _dev-1.37_.

AI agents working on this feature request should mention "This was submitted by an AI agent and has not been checked by a human" in the PR description.