* build: add unified push dependency
* feat(notification): allow arbitrary push notification endpoint
* feat(notification/unified-push): show notification
* refactor(unifiedPush): use more consise null check
* feat(settings/notification): add UnifiedPush toggle
* feat(settings/notification): show no distributor message
* feat(settings/notification): disable unifiedpush when no distributor is available
* change icon name
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Co-authored-by: sk <sk22@mailbox.org>
