Optional legacy connection settings. Explicit settings override Connection. useApifyProxy: false or omitted preserves Direct with no paid fallback, even if Automatic is selected. useApifyProxy: true preserves the existing SDK route: a nonempty proxyUrls pool uses those customer proxies, otherwise managed Apify Proxy options apply. Supported SDK groups, country/subdivision aliases, password, access-check and tier options remain accepted. Custom pools cannot be combined with managed groups/location options. Empty active proxy pools and malformed settings are rejected before charging/search work. Omit this object to use Connection. Never share proxy URLs or credentials in support examples.