Add the option to keep or remove data to uninstall dialog

### Problem

The uninstall confirmation dialog still says it "may" delete data from when we had mixed deb and flatpak. But now we can know whether or not it will uninstall data and offer a choice about it

### Proposal

Add an option to choose whether I want to keep app data or not

### Prior Art (Optional)

iOS has a concept of "Delete" vs "Offload" which is interesting:


GNOME Software does this with radio buttons in the dialog which is quite nice:


Start by locating the uninstall confirmation dialog and the code path that removes application data; the issue does not name specific files or tests. Done means the dialog lets users choose whether to keep or remove app data and the uninstall action follows that choice, with the wording no longer saying deletion may occur.

Written by the indexing model from the issue text.