feat: add Git and Jujutsu gutter indicators

src/ruby_config.rb

@@ -137,6 +137,7 @@ module Vamp
       @file_explorer_view = "tree"
       @clipboard_mode = "system"
       @git_blame = true
+      @git_gutter = "bar"
       @bar = BarConfig.new
       @popup = PopupConfig.new
       @labels = {}
@@ -197,6 +198,14 @@ module Vamp
       @git_blame = enabled
     end
 
+    # @param style [String] "bar", "symbols", "line_numbers", or "none"
+    def git_gutter=(style)
+      style = nonempty_string!(style, "git gutter")
+      raise ArgumentError, "git gutter must be bar, symbols, line_numbers, or none" unless %w[bar symbols line_numbers none].include?(style)
+
+      @git_gutter = style
+    end
+
     # @param values [Hash{String, Symbol => String}]
     # @return [Hash]
     def labels=(values)
@@ -275,6 +284,7 @@ module Vamp
         "leader" => @leader, "file_explorer_side" => @file_explorer_side, "file_picker_view" => @file_picker_view,
         "file_explorer_view" => @file_explorer_view, "clipboard_mode" => @clipboard_mode,
         "git_blame" => @git_blame,
+        "git_gutter" => @git_gutter,
         "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,