[rush] Support pnpm `configDependencies` and `updateConfig` in pnpmfile

[njxue]

Feature Request: Support pnpm 10's configDependencies and updateConfig in pnpmfile

Summary

Rush currently does not provide a supported mechanism to declare pnpm configDependencies such as globalConfigDependencies.

pnpm supports configuration plugins via configDependencies and the new updateConfig hook in pnpmfile:
https://pnpm.io/config-dependencies
https://pnpm.io/pnpmfile#hooksupdateconfigconfig-config--promiseconfig

These are required for enabling pnpm plugins such as @pnpm/plugin-esm-node-path, which are used in pnpm’s global virtual store mode:
https://pnpm.io/11.x/global-virtual-store

Because Rush does not support these features, pnpm’s configuration plugin system cannot be used cleanly in Rush-managed repositories.

---

Problem

There is no Rush-supported way to:

• declare configDependencies
• use pnpmfile updateConfig hook in a supported way

As a result:

• pnpm configDependencies cannot be installed in a structured way
• global virtual store setups requiring pnpm plugins are blocked or require workarounds (packageExtensions)

---

Proposed Solution

1. Support globalConfigDependencies

Introduce a Rush-level configuration field (e.g. in common/config/rush/pnpm-config.json):

{
  "globalConfigDependencies": {
    "@pnpm/plugin-esm-node-path": "0.1.2"
  }
}

Or rush-pnpm add --config @pnpm/plugin-esm-node-path should add @pnpm/plugin-esm-node-path under configDependencies in common/temp/pnpm-workspace.yaml

2. Support updateConfig hook in common/config/rush/.pnpmfile.cs

module.exports = {
  hooks: {
    readPackage,
    updateConifg, // new hook
  }
};