Add StandardRB and get some fixes

exe/ppkg

@@ -1,15 +1,15 @@
 #!/usr/bin/env ruby
 
 # Add lib directory to load path
-lib_path = File.expand_path('../lib', __dir__)
+lib_path = File.expand_path("../lib", __dir__)
 $LOAD_PATH.unshift(lib_path) unless $LOAD_PATH.include?(lib_path)
 
-require 'picopackage'
+require "picopackage"
 
 begin
   Picopackage::CLI.run(ARGV)
 rescue => e
   warn "Error: #{e.message}"
-  warn e.backtrace if ENV['DEBUG']
+  warn e.backtrace if ENV["DEBUG"]
   exit 1
 end