I think if you have something in writing that shows that this is a problem you highlighted whilst the car was in warranty and the dealer didn't pick it up when being serviced, then I think you'd have a case for arguing they should have spotted it then and fixed it. However, your case may be weakened if you got the car back after being serviced and it still had this fault but you didn't tell them straight away.
If you drive the car around fairly slowly on smooth ground whilst turning the wheel from side to side then the clicking or grinding would be CV joint or bearing. A suspension joint knocking would show up going over bumps, although I've also had knocking when I've forgotten to tighten the wheel nuts!
If the dealer won't fix it as a gesture of goodwill you can always imply that if they don't, you won't use them for any servicing in the future.