We went to Cavtat last year and although we didnt stay AI (we were in a villa) I know there were 2 hotels there that did it. Jet2 went to one of them and the other was a huge 5star place that looked lovely. Cant remember the names but would look them up if you wanted to know any more.
There are LOTS. Where/when are you going? You do know you've got basically 3 areas of Croatian coast - Istria (the big peninsula at the north end) Dalmatia (the long strip where Zadar, Split & Dubrovnik are) and then all the islands. ALL of them have loads of all-inclusive options. We often go to Istria. Check several coastal towns - Umag, Novigrad, Porec & lots of others, all good family spots full of all-inclusive hotels.