Add new Omarchy icon for fastfetch (#996)

* Add omarchy icon to fastfetch config

* Add migration file for fastfetch update

* Use consistent branding placement for spots you can change

* Allow editing the about icon

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Co-authored-by: David Heinemeier Hansson <david@hey.com>

install/config/branding.sh

@@ -0,0 +1,5 @@
+#!/bin/bash
+
+mkdir -p ~/.config/omarchy/branding
+cp ~/.local/share/omarchy/icon.txt ~/.config/omarchy/branding/about.txt
+cp ~/.local/share/omarchy/logo.txt ~/.config/omarchy/branding/screensaver.txt