fix: implement CSRF protection for remote function requests

[PuruVJ]

Closes #14791

As discussed, this makes sure the remote functions respect csrf.trustedOrigins. If trustedOrigins includes *, then any origin is allowed.

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[PuruVJ]

Admission: The tests are LLM written, lemme know if they're complete garbage 🤣😅

[PuruVJ]

Any update? 😁