Well if i'm correct , when your web:"no" then your public Url is not accessible and when you try to use it through another action then "it still doesn't work " , and your require-adobe-auth: false that means there is no security , it would be great if explain what you really want to do here ....I might not be able to understand this question properly
That “sign in” dialog is not coming from your YAML settings, it’s your browser doing HTTP basic auth against the Runtime endpoint.
Two key points:
web: 'no' makes this a non‑web action. Non‑web actions are not meant to be opened directly in the browser; Runtime protects them with basic auth and expects namespace credentials.
require-adobe-auth: false only affects web actions; it does not remove that basic auth challenge for web: 'no' actions.
So:
If you want to hit the action via a URL / browser, change it to a web action: