fix: Add backward compatibility for YAML.load_file across Psych versions

The `YAML.load_file(path, aliases: true)` syntax works on Ruby 3.4+ with
Psych 5+, but raises ArgumentError on older Ruby/Psych versions that don't
support the aliases parameter.

Added graceful fallback with rescue to support all Ruby versions:
- Try loading with `aliases: true` first (Psych 5+)
- Fall back to `YAML.load_file(path)` on ArgumentError (older Psych)

This ensures the generator works across all supported Ruby versions without
breaking CI on older Ruby environments.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: justin808

lib/generators/react_on_rails/base_generator.rb

@@ -412,8 +412,13 @@ def configure_rspack_in_shakapacker
         puts Rainbow("🔧 Configuring Shakapacker for Rspack...").yellow
 
         # Parse YAML config properly to avoid fragile regex manipulation
-        config = YAML.load_file(shakapacker_config_path, aliases: true)
-
+        # Support both old and new Psych versions
+        config = begin
+          YAML.load_file(shakapacker_config_path, aliases: true)
+        rescue ArgumentError
+          # Older Psych versions don't support the aliases parameter
+          YAML.load_file(shakapacker_config_path)
+        end
         # Update default section
         config["default"] ||= {}
         config["default"]["assets_bundler"] = "rspack"