add ghostty config and theme

configs/ghostty_g/themes/GruvboxDark

@@ -0,0 +1,21 @@
+palette = 0=#282828
+palette = 1=#cc241d
+palette = 2=#98971a
+palette = 3=#d79921
+palette = 4=#458588
+palette = 5=#b16286
+palette = 6=#689d6a
+palette = 7=#a89984
+palette = 8=#928374
+palette = 9=#fb4934
+palette = 10=#b8bb26
+palette = 11=#fabd2f
+palette = 12=#83a598
+palette = 13=#d3869b
+palette = 14=#8ec07c
+palette = 15=#ebdbb2
+background = 282828
+foreground = ebdbb2
+cursor-color = ebdbb2
+selection-background = 665c54
+selection-foreground = ebdbb2