will bark if the doorbell rings or somebody knocks.
That's what dogs are supposed to do!
I would decide a strategy for where to put Amber if someone comes to the door (in a crate/shut in another room etc) so you're prepared in future, and as you consistently put her in the same place every time she'll eventually get used to it.
Saying that, I think she behaved prefectly normally in becoming protective of your home when a stranger opened the door; I'd be horrified if my window cleaner opened my door and he wouldn't dream of doing so! If he had been bitten, there is no way you would have been liable and imo he would have deserved it
I'd be changing window cleaners, not worrying about your dog, if I were you.