Add new scriptlet — append/load scripts

[AdamWr]

Sometimes apps cannot detect source of the request, so we need a scriptlet which we load these scripts, so source will be detected.

For example here - https://github.com/AdguardTeam/AdguardFilters/issues/110659 Source of connatix.com script is not detected, so we cannot easily fix it with apps.

Screenshot

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Another case - https://github.com/AdguardTeam/AdguardFilters/issues/109135 After clicking on "Produkt bewerten" button, mpsnare.iesnare.com/snare.js is loaded and source is not detected.

Screenshot