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

---------

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

config/fastfetch/config.jsonc

@@ -1,9 +1,13 @@
 {
   "$schema": "https://github.com/fastfetch-cli/fastfetch/raw/dev/doc/json_schema.json",
   "logo": {
+    "type": "file",
+    "source": "~/.config/omarchy/branding/about.txt",
+    "color": { "1": "green" },
     "padding": {
-      "top": 5,
-      "right": 6
+      "top": 2,
+      "right": 6,
+      "left": 2
     }
   },
   "modules": [