Fix helix theme's word selection colors (#5630)

* Fix helix theme's word selection colors

Without this fix, if users enabled `editor.cursorline`, the word
selection would not be visually distinct from the cursorline selection.

Closes: https://github.com/basecamp/omarchy/issues/5580
Signed-off-by: Luke Hsiao <luke@hsiao.dev>

* Make Retro-82 color0 visually distinct from background

Signed-off-by: Luke Hsiao <luke@hsiao.dev>

* Make matte-black selection background distinct from color0

Signed-off-by: Luke Hsiao <luke@hsiao.dev>

---------

Signed-off-by: Luke Hsiao <luke@hsiao.dev>

themes/matte-black/colors.toml

@@ -3,7 +3,7 @@ cursor = "#eaeaea"
 foreground = "#bebebe"
 background = "#121212"
 selection_foreground = "#bebebe"
-selection_background = "#333333"
+selection_background = "#515151"
 
 color0 = "#333333"
 color1 = "#D35F5F"

themes/retro-82/colors.toml

@@ -15,7 +15,7 @@ selection_foreground = "#00172e"
 selection_background = "#faa968"
 
 # Normal colors (ANSI 0-7)
-color0 = "#00172e"
+color0 = "#303442"
 color1 = "#f85525"
 color2 = "#028391"
 color3 = "#e97b3c"