Fix RuboCop offenses and enable PR checks

.github/workflows/rubocop.yml

@@ -4,6 +4,9 @@ on:
   push:
     branches:
       - main
+  pull_request:
+    branches:
+      - main
 
 jobs:
   rubocop:

config/application.rb

@@ -10,7 +10,7 @@ module CodeLearnApi
   class Application < Rails::Application
     # Initialize configuration defaults for originally generated Rails version.
     config.load_defaults 7.0
-    
+
     # Disable freezing of autoload_paths and eager_load_paths for Rails 8.1 compatibility
     # with older gems that try to modify these arrays
     config.autoloader = :zeitwerk

config/boot.rb

@@ -6,7 +6,7 @@
 # Monkey patch Array to prevent freezing errors in Rails 8.1
 # This allows older gems to modify frozen autoload_paths arrays
 class Array
-  alias_method :original_freeze, :freeze
+  alias original_freeze freeze
 
   def freeze
     # Check if this array is being set as autoload_paths or eager_load_paths