Enhance server bundle path resolution logic

- Updated the logic for determining server bundle paths to include a fallback mechanism that checks for the existence of paths based on the `enforce_private_server_bundles` configuration.
- This change ensures that if the enforcement is not active, the system will attempt to return the first valid path from a list of candidate paths, improving robustness in asset management.

This update aligns with recent changes to clarify the handling of server bundles and enhances the overall functionality of the asset resolution process.

Author: AbanoubGhadban

lib/react_on_rails/utils.rb

@@ -121,7 +121,15 @@ def self.bundle_js_file_path(bundle_name)
 
       # For server bundles with server_bundle_output_path configured, use that
       if is_server_bundle && config.server_bundle_output_path.present?
-        return File.expand_path(File.join(root_path, config.server_bundle_output_path, bundle_name))
+        candidate_paths = [File.expand_path(File.join(root_path, config.server_bundle_output_path, bundle_name))]
+        unless config.enforce_private_server_bundles
+          candidate_paths << File.expand_path(File.join(root_path, config.server_bundle_output_path, bundle_name))
+        end
+
+        candidate_paths.each do |path|
+          return path if File.exist?(path)
+        end
+        return candidate_paths.first
       end
 
       # For client bundles and server bundles without special config, use packer's public path