Category can be assigned and added using menu

[Misiu]

Now we have two menu items that we can use to Assign or Add a Category.
There is an Assign category menu item, which allows us to assign a category, but we can also add a category from the Rename menu.

Also, the Rename button doesn't feel right. For example, if you only want to edit labels or add a description, you're not renaming the automation; you're editing its metadata.