Upgrade package manager from pnpm 10 to pnpm 11

Overview

This issue tracks the upgrade of the package manager from pnpm 10 to pnpm 11.

pnpm 11 Release Notes

• Blog post / release notes: https://pnpm.io/blog/releases/11.0
• Migration guide (v10 → v11): https://pnpm.io/blog/releases/11.0#migrating-from-v10-to-v11
• GitHub releases: https://github.com/pnpm/pnpm/releases

Key Changes in pnpm 11

• Node.js 22+ required — support for Node.js 18, 19, 20, and 21 is dropped. pnpm is now pure ESM.
• Supply-chain protection on by default — minimumReleaseAge defaults to 1 day (1440 min) and blockExoticSubdeps defaults to true.
• allowBuilds replaces legacy build-dependency settings — onlyBuiltDependencies, neverBuiltDependencies, ignoredBuiltDependencies, and ignoreDepScripts are removed.
• Configuration split — .npmrc is now auth/registry only; all other pnpm settings must live in pnpm-workspace.yaml or the new global ~/.config/pnpm/config.yaml.
• New SQLite-backed store index (store v11) — replaces JSON-per-package index for faster installs.
• Native publish flow — pnpm publish, login, logout, etc. no longer delegate to npm CLI.
• Isolated global installs via the global virtual store.
• New commands — pnpm ci, pnpm sbom, pnpm clean, pnpm peers check, pnpm runtime set, and short pn/pnx aliases.
• Environment variables use pnpm_config_* prefix instead of npm_config_*.

Required Changes in This Repository

1. Update packageManager field in package.json to pnpm@11.x.x.
2. Migrate pnpm-workspace.yaml — replace allowBuilds: false entries with the new allowBuilds model; note that strictDepBuilds and related legacy fields are removed.
3. Ensure CI environment uses Node.js 22+.
4. Review any .npmrc settings and move non-auth config to pnpm-workspace.yaml.
5. Update the lockfile (pnpm-lock.yaml) by running pnpm install after the upgrade.
6. Update scripts/check-pm.js if needed (the npm_config_user_agent env var logic may need updating since pnpm 11 uses pnpm_config_* prefix for its own settings).

Context

This issue was raised in the context of PR #145, which introduced pnpm 10 as the package manager.

Requested by: @infeo