Grammarly Inc., the maker of artificial intelligence-powered writing assistance software, is acquiring productivity startup Coda in a deal that will also bring it a new chief executive officer.Coda co-founder and CEO Shishir Mehrotra will take over that position at Grammarly, according to statement from the two companies Tuesday. Grammarly’s current top executive, Rahul Roy-Chowdhury, will remain on the board....