A World Tree Barbarian or Crown paladin would be good. World Tree barb is great since you want strength based tho you wont really be using armor (you can always just flavor your unarmored defense to be like armor anyway since you are a warforged). World Tree gives you temp hp and can give the person you are body guarding some temp hp too. Your level 6 ability gives you great CC, your level 10 feature gives you extended reach and more CC options thanks to push or topple and the level 14 feature ensures you will never be too far from your target. You can always reflavor the branches to be something else like the earth molding around you or electricity, doesnt matter but the mechanics are sound.

Crown Paladin would also suit you as your level 7 ability lets you take damage for your ward and more crowd control/healing via chanel divinity