[FEATURE] Filter websites that doesn't have CORS

[kvnzrch]

Describe the feature you'd like to see added
What the title says, that at least, you can do a fetch for each URL, to show if it has the headers that prevent that URL from being displayed inside an iframe. Perhaps it can be activated through environment variables, and that next to each URL, in the results list, a Loader is shown, and then nothing if it can be embedded or a green check, or an red X if it cannot.

Additional context
I'm making an app that simulates a desktop environment, with Whoogle as the home page ❤️. Almost all pages block the ability to embed in an iframe, that's the issue.