Not an electrician, and yet was thinking that the fuses in the consumer distribution box is supposed to do this. But no, then recalled that one of my vacuum cleaners died recently - Overheated; I had been cleaning the main canister but did not think that the rear hepa filter would become clogged the way it did. So it didn't trip the New fuses I'd recently installed i.e. RCBO's. The vacuum cleaner then overheated and died.
With the damage that you have mentioned, I"d be thinking that the steamer is already dead. If you rewired and plugged it back in, you could at least tell if it works still. Sorry to see that no one with electrical knowledge has answered your question specifically relating to what size, type etc fuse to put in; inclusive why the manufacturer did not incorporate this. Thankfully my vacuum cleaner only cost me $50 with shipping off of ebay; a pretty good one for the money, but obviously a lesson to maintain things prior to use.