I have a hook but catch no fish, and a boom but play no music. I'm called when you're in a bind, to give your car a helping hand. What am I?

I carry treasure without a map, Built from boards with metal straps. In attics, ships, or games I wait, bountiful treats I will surely give

An emergency staple, one you can't do without, especially if the power goes out.

Mixed and kneaded, left to rest, I grow with air inside my chest. Then baked until my crust is made, a golden staple that won’t soon fade.

I have skin but no bones, a mouth but no teeth, and I swallow your secrets while hanging from your arm. I sometimes have a hand in me, I also have a hand in my name. What am I?