What platform are you using while running the build process?
npm run build
is the command you are looking for, but your development environment might need so additional configuration.
This is what is being used to generate the standalone apps. Maybe the docs might help?
In my testing all three executables compile correctly in macOS.
$ npm run build
> chrome-capture-for-channels@1.0.0 build chrome-capture-for-channels
> pkg .
> pkg@5.8.1
> Fetching base Node.js binaries to PKG_CACHE_PATH
fetched-v18.5.0-macos-arm64 [====================] 100%
fetched-v18.5.0-macos-x64 [====================] 100%
fetched-v18.5.0-win-x64 [====================] 100%
$ ls -l dist
chrome-capture-for-channels-macos-arm64
chrome-capture-for-channels-macos-x64
chrome-capture-for-channels-win-x64.exe
Most of the code in script/build is related to signing the mac executables so they can run without security warnings.