PM2 module installation should support other package managers

node -v  # v24.20.0
pnpm -v  # 12.3.1
npm -v   # NOT FOUND — zsh: npm: 명령을 찾을 수 없습니다...
pm2 -v   # 7.0.4

pm2 install pm2-logrotate

The error happens in /pm2/lib/API/Modules/NPM.js:

[PM2][Module] Calling [NPM] to install pm2-logrotate ...
node:child_process:585
  validateString(file, 'file');
  ^

TypeError [ERR_INVALID_ARG_TYPE]: The "file" argument must be of type string. Received null
    at normalizeSpawnArguments (node:child_process:585:3)
    at spawn (node:child_process:806:13)
    at /home/hyunbinseo/.local/share/pnpm/global/v11/525b6-18d2725b77324f18-0/node_modules/.pnpm/pm2@7.0.4_supports-color@7.2.0/node_modules/pm2/lib/API/Modules/NPM.js:216:74 {
  code: 'ERR_INVALID_ARG_TYPE'
}

Node.js v24.20.0

npm might not exist in the system, so respecting the package manager used to install PM2 would be nice.

Installing a Node.js runtime via node@runtime:<version> (including pnpm env use and pnpm runtime set node) no longer extracts the bundled npm, npx, and corepack from the Node.js archive.

https://pnpm.io/blog/releases/11.0#slimmer-runtime-installs

Start in /pm2/lib/API/Modules/NPM.js, especially the spawn call around line 216, and reproduce the reported pm2 install pm2-logrotate failure in an environment with pnpm but no npm. Trace how the package manager executable is selected; done means module installation works when npm is unavailable and uses the package manager available to PM2.