When copy-pasting in the same folder in the browse UI ask for target name

Currently when copy-pasting in the same folder the new file gets the name `original-copy` first and is then typically renamed to the desired name. Because Helix 6 will not have a native rename/move operation following the current approach will create a lot of churn, as first the file with the wrong name is created, then this file would be copied to the file with the desired name and then the file with the `original-copy` name will be deleted.

It would be better to open a dialog to ask for the target name in this case, as then the copy could just copy the file to the right name in the first place and we would save one copy and one delete operation.

Start by tracing the browse UI's copy-paste flow and the branch that handles copying within the same folder. Inspect existing dialog patterns before changing the interaction. Done means same-folder paste asks for the target name and creates the copy directly with that name, avoiding the intermediate copy and delete operations.

Written by the indexing model from the issue text.