When npm fails or is not installed, ptp.py does not report an error, and indicates that the operation was successful.

[S4lt5]

The pyp.py operation at https://github.com/cisagov/rva-reporting-engine/blob/f456d4c47dfeb100b5e38cd91f6f36c8f2cd5165/ptp.py#L317

failed on my machine as there is no host-level npm command, but said that everything worked, and blissfully continued on.

❯ which  npm
npm not found
❯ ./ptp.py dev -r RVA
PT Portal
Loading PT Portal with docker-compose for developers
composing environment variable file for docker-compose
Installing SDS and running postcss for tailwind.
/bin/sh: npm: command not found
/bin/sh: npm: command not found
Successfully installed SDS and tailwind.

The install process should check to see if the npm commands were successful before moving on.

This is missing from the README entirely and should state in prerequisites that it needs to be installed since it is not obvious that this project that appears to be primarily python-based container project needs host-level nodejs installed, and that we'd need the right things in our build image / CI to proceed.