The entries/groups from the other keepass database to other database

Hello,

it would be very nice if there were a function to open another database next to the first one.

Users can then copy their selected entries or groups back and forth.

The issue names no files, tests, or entry points. First map the Android database-opening and entry/group editing flows, then clarify the multi-database interaction and copying behavior; done means users can open a second KeePass database and copy selected entries or groups between databases.

Written by the indexing model from the issue text.