By Kritika Lamba and Jaspreet Singh Dec 23 (Reuters) - ServiceNow on Tuesday agreed to buy cybersecurity startup Armis for $7.75 billion, in the ​enterprise software maker's biggest-ever deal, as it bolsters its services ‌to help counter rising cyberattacks driven by AI adoption. Through the deal, the company aims to ‌integrate Alphabet-backed Armis' security features such as device scanning and threat detection, a crucial advantage amid sophisticated cyberattacks that have hit companies ranging from Mic ...