fix: highlight NonText characters (#547)

Author: mrtnvgr

lua/catppuccin/groups/editor.lua

@@ -52,7 +52,7 @@ function M.get()
 		Search = { bg = U.darken(C.sky, 0.30, C.base), fg = C.text }, -- Last search pattern highlighting (see 'hlsearch').  Also used for similar items that need to stand out.
 		IncSearch = { bg = U.darken(C.sky, 0.90, C.base), fg = C.mantle }, -- 'incsearch' highlighting; also used for the text replaced with ":s///c"
 		CurSearch = { bg = C.red, fg = C.mantle }, -- 'cursearch' highlighting: highlights the current search you're on differently
-		SpecialKey = { fg = C.text }, -- Unprintable characters: text displayed differently from what it really is.  But not 'listchars' textspace. |hl-Whitespace|
+		SpecialKey = { link = "NonText" }, -- Unprintable characters: text displayed differently from what it really is.  But not 'listchars' textspace. |hl-Whitespace|
 		SpellBad = { sp = C.red, style = { "undercurl" } }, -- Word that is not recognized by the spellchecker. |spell| Combined with the highlighting used otherwise.
 		SpellCap = { sp = C.yellow, style = { "undercurl" } }, -- Word that should start with a capital. |spell| Combined with the highlighting used otherwise.
 		SpellLocal = { sp = C.blue, style = { "undercurl" } }, -- Word that is recognized by the spellchecker as one that is used in another region. |spell| Combined with the highlighting used otherwise.