Make copy to clipboard and save to file work

[kdzwinel]

Currently context menu is useless ("copy All as HAR" / "copy as cURL" / "Save as file") - it does work, it just doesn't copy stuff to your 📋 because implementation for that is missing in the "hosted mode":

WebInspector.console.error("Clipboard is not enabled in hosted mode. Please inspect using chrome://inspect");

It's electron though, we can make it work!