Add support for Ripple panic button

Currently KeePass DX is not compatible with Ripple, it would be really nice and helpful for both projects if support would be added. KP DX would have an extra layer of security and Ripple would have one more app that has support, and this would incentivize Ripple's devs to continue with their work.

It would be even greater it you could add a setting to delete the entries, not just to hide the app when triggered. A lot of apps have support for it but only enable this option, which is kind of lame since it can have a bigger potential.

Thanks!

The issue names no files, tests, or entry points. First clarify Ripple's panic-button integration requirements and whether deletion must be reversible or permanent; done means KeePass DX responds to the trigger and provides the requested hide-or-delete behavior.

Written by the indexing model from the issue text.