Feature: Option to delete non-empty Project

[benjaminbauer]

Status quo

Given I have a project with more than one thread
When I want to delete the project
Then the UI blocks that, asking me to delete all threads first

Proposal

Instead of the notification, open a dialog to confirm deletion of non-empty project: "Deleting <project> will also delete all threads" -> confirm/cancel

[binbandit]

Hopefully, #651 will help address this issue in the meantime. It will allow you to bulk select project threads and delete them.