Allow customizing the screensaver logo (#863)

* check for custom screensaver logo or fall back to default

* move logo location to omarchy config folder

* fix missed location check

* add menu item to copy logo.txt and open in editor

* move to setup menu

* Just always use a user-editable screensaver.txt file

* No longer needed

* Be clearer

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Co-authored-by: Christopher Moore <cmoore@yozu.co.uk>
Co-authored-by: David Heinemeier Hansson <david@hey.com>

bin/omarchy-restart-walker

@@ -4,3 +4,4 @@ pkill walker
 # FIXME: Reenable the walker service once the memory leak has been fixed
 # See https://github.com/basecamp/omarchy/issues/698
 # setsid uwsm app -- walker --gapplication-service &
+echo # Always end in success so we don't terminate further running