Is there some light program/script that allows to generate bitcoin addresses, as well as converting address/private key to/from QR code (image file), and it'll be awesome if it supports mini private key format as well.
Ideally I'm looking for libraries to use in my project, but if they're stand alone CLI I can still manage to use them.
A year ago, I've been playing around with miniprivatekey.py, bitcoin-tool and qrencode. I used this to search for mini private keys with vanity addresses.
Combined together, these 3 programs can do most of what you're looking for.
Update: I think I made up the name "miniprivatekey.py", so it's not helping you. I used
this script. The rest of the programs can easily be found.
Note: I haven't used this for anything holding actual funds. I'll leave it up to you to make sure it's secure and random enough.