A simple app that solves the problem with using fingerprint scanning in Termux on Android 14.
The app opens a fingerprint scanner (for unlocking keys from secured hardware keystore), then sends the result to a local server (which should be launched by the user via Termux with a script; the script can be found in the GitHub repository, see the link below), after which the application closes.
More details, the helper script, and source code can be found in the GitHub repository: https://github.com/flameshikari/termux-fingerprint