So far as I am aware there’s not much you can do other than replace the glass. 😕
I’ve never seen a polishing kit for ceramics, only specialist cleaners for them. The glass is quite “soft” so it would be easily scratched by the likes of an abrasive cleaner and probably that’s why I’ve never seen sucha thing.
And the ceramic tops, generally, cost a small fortune!
The most popular ceramic hob glass used by many manufacturers is produced by Ceran based in Germany. Very tough and reliable over many years of use and abuse usually. Sugar spillage is the biggest headache for damaging the glass surface and in severe circumstances renders the glass irrepairable. Use good quality products specifically formulated for ceramic glass care and nothing else.