If you want to stay with the convenience of cloud without going back to sync conflicts due to moving a file around, Proton Pass is GPLv3 although I don't personally know what the self hosting story is like if they were to rug pull
https://github.com/ProtonMail/WebClients/tree/proton-pass%40...
https://github.com/protonpass/android-pass/blob/1.26.1/LICEN...