Scrape a Google search SERP for organic + ad results

Runs a Google web search for keyword and returns a normalized JSON structure with topAds, bottomAds, organic results, totalResults, aiOverview (Google's AI-written summary and the hostnames it cites, or null when the search has none), and the proxy country actually used. Set pages_to_check 1-10 to paginate. wait_after_load adds a delay after the SERP loads (useful for sites where ads render late); captcha_pause lets you eyeball / solve a CAPTCHA when running interactively.