Retrieves detailed information about a specific LinkedIn ad by URL. Returns id, description, headline, adType, advertiser, and targeting with language, location, and audience criteria. Also includes totalImpressions, impressionsByCountry, adDuration, startDate, and endDate. Date and impression fields are nullable when LinkedIn does not expose them on the public ad page. The existing image, video, organicVideo, preRollVideo, and carouselImages fields keep their previous values. paidForBy is the public paying entity when LinkedIn shows one, without the 'Paid for by' prefix. targetingTable lists Uses the caller's OpenAny gateway credentials. Charges and authorization are determined by the gateway.