pants run for nodejs only works if package.json in root directory

[kdowney-talos]

Describe the bug
The pants run goal fails with:

(.venv) serenitydev@c774de47c447:~/bug_report$ pants run //serenity.middleware:js#generate-asyncapi
15:11:54.20 [INFO] Completed: Installing [email protected].
yarn run v1.22.10
error Couldn't find a package.json file in "/tmp/pants-sandbox-YWbbQa"
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.

if and only if the package.json is in a sub-directory in the monorepo; if at root next to pants.toml, it works.

See details below for fully reproducible test case.

Pants version
2.25.0.dev2 (also observed in 2.23.x)

OS
Ubuntu 22.04 as dev container hosted inside VS Code on MacOS 15.2 (ARM64)

Linux c774de47c447 6.10.14-linuxkit #1 SMP Fri Nov 29 17:22:03 UTC 2024 aarch64 aarch64 aarch64 GNU/Linux

Additional info

pants.toml

[GLOBAL]
pants_version = "2.25.0.dev2"
backend_packages = [
  "pants.backend.experimental.javascript",
]

[nodejs]
version = "v22"

BUILD

package_json(
    name="js",
    source="package.json",
    scripts=[
        node_build_script(entry_point="generate-asyncapi"),
    ],
)

package.json

{
    "name": "asyncapi-generator",
    "version": "0.0.1",
    "description": "Stub to install AsyncAPI Generator",
    "private": true,
    "type": "module",
    "scripts": {
        "generate-asyncapi": "asyncapi generate model"
    },
    "dependencies": {
        "@asyncapi/generator": "^1.0.0"
    },
    "packageManager": "[email protected]"
}

If you put these three files in the same directory and run:

pants run //:js#generate-asyncapi

You'll get an error like this (expected -- bad run command):

(.venv) serenitydev@c774de47c447:~/bug_report$ pants run //:js#generate-asyncapi
yarn run v1.22.10
$ asyncapi generate model
/bin/sh: 1: asyncapi: not found
error Command failed with exit code 127.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.

but if you simply move BUILD and package.json into a sub-directory, it fails with the reported error:

(.venv) serenitydev@c774de47c447:~/bug_report$ mkdir serenity.middleware
(.venv) serenitydev@c774de47c447:~/bug_report$ mv BUILD package.json serenity.middleware/
(.venv) serenitydev@c774de47c447:~/bug_report$ pants run //serenity.middleware:js#generate-asyncapi
yarn run v1.22.10
error Couldn't find a package.json file in "/tmp/pants-sandbox-AcIIZR"
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.

My expectation is that each sub-directory in a monorepo will be treated as a standalone module, and that package.json does not have to be globally available at root. For our project I can work around this -- we only have have module which requires NodeJS, and it's for installing a CLI code generation tool --but it seems out of step with the rest of Pants.