Use Exception#detailed_message hook for lazy loading error enhancer gems

Prepend an Exception::DetailedMessage module that loads error_highlight,
did_you_mean, and syntax_suggest on first detailed_message call, then
removes itself from the method chain to avoid double dispatch.

Guard with defined?(Ruby::DetailedError) to handle cases where the
constant may not be available in the current execution context.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: hsbt

gem_prelude.rb

@@ -36,14 +36,18 @@ def self.load
         warn "`syntax_suggest' was not loaded."
       end if defined?(SyntaxSuggest)
     end
+  end
 
+  module Exception::DetailedMessage # :nodoc:
     def detailed_message(...)
-      return super if Ruby::DetailedError.loaded?
-      Ruby::DetailedError.load
-      # Re-dispatch to pick up the newly prepended methods from the gems
-      detailed_message(...)
+      if defined?(Ruby::DetailedError)
+        Ruby::DetailedError.load
+        Exception::DetailedMessage.remove_method(:detailed_message)
+        detailed_message(...)
+      else
+        super
+      end
     end
   end
-
-  Exception.prepend(Ruby::DetailedError)
+  Exception.prepend(Exception::DetailedMessage)
 end