Enable Light/Dark Mode Toggle (nephio-project#273)

Adding light/dark mode themes to documentation as user prefers.
Toggle Button is in the top right corner and can be viewed in preview.
It should auto adjust to the users browser settings

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Co-authored-by: JamesMcDermott <james.j.mcdermott@ericsson.com>

Author: 2 people

assets/scss/_styles_project.scss

@@ -0,0 +1 @@
+@import 'td/code-dark';

config.toml

@@ -45,9 +45,9 @@ enableMissingTranslationPlaceholders = true
       unsafe= true
     [markup.highlight]
 
-      # See a complete list of available styles at https://xyproto.github.io/splash/docs/all.html
+      # Setting no default style; allows style to auto adjust between light and dark default markdown themes
 
-      style = "tango"
+      noClasses = false
 
       # Uncomment if you want your chosen highlight style used for code blocks without a specified language
 
@@ -124,6 +124,10 @@ offlineSearchMaxResults = 10
 
 [params.ui]
 
+# Enable Visibility of Light/Dark Mode Toggle
+
+showLightDarkModeMenu = true
+
 # Enable to show the side bar menu in its compact state.
 
 sidebar_menu_compact = true