fix: add spaces between directory and file names in ls output

lib/packages/ls.rb

@@ -1,6 +1,10 @@
 require 'set'
 require_relative 'core'
 
+# The Ls class simulates a simplified version of the Unix 'ls' command,
+# listing files and directories in the current working directory.
+# It includes options for showing all files, including hidden ones,
+# or just non-hidden files by default.
 class Ls
   def self.main params
     # Create new instance of Ruby data structure Set to add output to it
@@ -24,7 +28,7 @@ def self.main params
     end
 
     # Use the Core class of ShellRB to print result
-    Core.print_result result
+    Core.print_result prepared_result result
     result
   end
 
@@ -49,4 +53,13 @@ def self.show_non_hidden
     end
     non_hidden
   end
+
+  def self.prepared_result unprepared_result
+    array = unprepared_result.to_a
+
+    array.each_with_index do |entry, index|
+      array[index] = "#{entry} " unless index == array.size - 1
+    end
+    Set.new(array)
+  end
 end