Propose error-avoiding filename on new file creation

[hurradieweltgehtunter]

Steps to reproduce

1. Click on button New -> text file
2. Do not alter proposed filename ("New file.txt")
3. Hit "Create"
4. Click again on button New -> text file

Expected behaviour

The current behaviour is not wrong but the user experience could be improved if the proposed filename would be "New file(2).txt" thus avoiding displaying an error.

Actual behaviour

Error message shows "New file.txt already exists"

Environment general

Operating system: https://ocis.ocis-wopi.latest.owncloud.works

[kulmann]

Good idea! We have the same logic anyway when the user chose "keep both" in a copy/move conflict situation. Could be reused here.

[AlexAndBear]

Fair enough, good catch!