feat: dim whitespace markers and configure scope and newlines

src/ruby_config.rb

@@ -144,6 +144,7 @@ module Vamp
       @scroll_distance = 0
       @highlight_trailing_whitespace = false
       @whitespace_characters = {}
+      @whitespace_scope = "all"
       @diff_context_lines = 10
       @diff_expand_lines = 15
       @diff_view_mode = "split"
@@ -244,6 +245,15 @@ module Vamp
       @whitespace_characters = characters.dup
     end
 
+    # @param scope [String] "all" or "leading"
+    # @return [String]
+    def whitespace_scope=(scope)
+      scope = Vamp.string!(scope, "whitespace_scope")
+      raise ArgumentError, "whitespace_scope must be all or leading" unless %w[all leading].include?(scope)
+
+      @whitespace_scope = scope
+    end
+
     # @param lines [Integer] nonnegative context lines around each diff change
     # @return [Integer]
     def diff_context_lines=(lines)
@@ -318,6 +328,7 @@ module Vamp
         "scroll_distance" => @scroll_distance,
         "highlight_trailing_whitespace" => @highlight_trailing_whitespace,
         "whitespace_characters" => @whitespace_characters,
+        "whitespace_scope" => @whitespace_scope,
         "top_bar" => @bar.top, "bottom_bar" => @bar.bottom, "labels" => @labels,
         "popup" => { "command" => @popup.command, "search" => @popup.search },
         "diff_context_lines" => @diff_context_lines, "diff_expand_lines" => @diff_expand_lines,