[FR]: Support for configDependencies in pnpm-workspace.yaml

### What is the current behavior?

There is a kind of dependency which we do not support yet called [configDependencies](https://pnpm.io/config-dependencies). As far as I can tell, we currently ignore it.

### Describe the feature

This came up during testing of pnpm 11, because the presence of `configDependencies` is one thing that can cause `pnpm-lock.yaml` to be a multi-document file. We are likely going to get pnpm 11 working by just ignoring the extra document, but it seems worth considering whether we should eventually add real support for this.

The issue names pnpm-workspace.yaml and pnpm-lock.yaml but no implementation files or tests. Start by locating the existing workspace and lockfile parsing entry points and compare their handling with pnpm's configDependencies format. Before coding, establish whether support means parsing the extra lockfile document or only avoiding breakage; done should be a defined behavior covered by tests.

Written by the indexing model from the issue text.