will magnets in my luggage affect air tags

If these are permanent magnets, then the answer is no. They would have no affect with the Bluetooth signal emitted by the AirTag. That signal would be more impeded by the material used in the construction of the luggage should you place the tag inside.

Yes, those shouldn't pose any issues. The only magnets that would, would be the electro-magnetic kind that require an electric current to activate them. Not very likely something you would carry in your luggage as they would require a very, very long extension cord. ;)

no