Add make style targets for Ruby

Client: rb

Run RuboCop safe autocorrection for the Ruby library, cross-language
tests, and tutorial through the existing Autotools style hooks.

Co-Authored-By: OpenAI Codex (gpt-6.1-sol) <codex@openai.com>

Author: kpumuk

lib/rb/Makefile.am

@@ -45,6 +45,9 @@ check-local: all
 
 endif
 
+style-local:
+	cd $(srcdir) && bundle exec rubocop -a
+
 dist-hook:
 	$(RM) -r $(distdir)/spec/gen-rb/
 

test/rb/Makefile.am

@@ -30,6 +30,9 @@ if HAVE_BUNDLER
 	$(BUNDLER) exec $(RUBY) -I. test_suite.rb
 endif
 
+style-local:
+	cd $(srcdir) && bundle exec rubocop -a --config ../../lib/rb/.rubocop.yml
+
 clean-local:
 	$(RM) -r gen-rb/
 

tutorial/rb/Makefile.am

@@ -28,6 +28,9 @@ tutorialserver: all
 tutorialclient: all
 	${RUBY} RubyClient.rb
 
+style-local:
+	cd $(top_srcdir)/lib/rb && bundle exec rubocop -a --config .rubocop.yml ../../tutorial/rb
+
 clean-local:
 	$(RM) -r gen-*