add ghostty config and theme

configs/ghostty_g/themes/Arthur

@@ -0,0 +1,21 @@
+palette = 0=#3d352a
+palette = 1=#cd5c5c
+palette = 2=#86af80
+palette = 3=#e8ae5b
+palette = 4=#6495ed
+palette = 5=#deb887
+palette = 6=#b0c4de
+palette = 7=#bbaa99
+palette = 8=#554444
+palette = 9=#cc5533
+palette = 10=#88aa22
+palette = 11=#ffa75d
+palette = 12=#87ceeb
+palette = 13=#996600
+palette = 14=#b0c4de
+palette = 15=#ddccbb
+background = 1c1c1c
+foreground = ddeedd
+cursor-color = e2bbef
+selection-background = 4d4d4d
+selection-foreground = ffffff