Type artifact_path as an Array

Review feedback: `is_string:` is deprecated. `type: Array` replaces both
it and most of the `verify_block`, and fastlane converts a String into
an array for us, so a single path still works — it splits on commas,
which means a path containing one would be read as two.

---

Generated with the help of Claude Code, https://claude.ai/code

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: mokagio

lib/fastlane/plugin/wpmreleasetoolkit/actions/macos/macos_verify_code_signing.rb

@@ -7,7 +7,7 @@ module Fastlane
   module Actions
     class MacosVerifyCodeSigningAction < Action
       def self.run(params)
-        paths = Array(params[:artifact_path])
+        paths = params[:artifact_path]
         UI.user_error!('No artifact to verify: `artifact_path` is empty') if paths.empty?
 
         paths.each do |path|
@@ -112,12 +112,9 @@ def self.available_options
           FastlaneCore::ConfigItem.new(
             key: :artifact_path,
             description: 'The path, or list of paths, to the `.app` bundle(s) or `.dmg` disk image(s) to verify',
-            is_string: false,
+            type: Array,
             verify_block: proc do |value|
-              next if value.is_a?(String)
-              next if value.is_a?(Array) && value.all?(String)
-
-              UI.user_error!('`artifact_path` must be a String or an Array of Strings')
+              UI.user_error!('`artifact_path` must be a String or an Array of Strings') unless value.all?(String)
             end
           ),
           FastlaneCore::ConfigItem.new(

spec/macos_verify_code_signing_spec.rb

@@ -229,7 +229,7 @@ def expect_stapler_validate(path, exitstatus: 0)
 
   it 'fails when `artifact_path` is neither a String nor an Array' do
     expect { run_described_fastlane_action(artifact_path: 42) }
-      .to raise_error(FastlaneCore::Interface::FastlaneError, /`artifact_path` must be a String or an Array of Strings/)
+      .to raise_error(FastlaneCore::Interface::FastlaneError, /'artifact_path' value must be either `Array` or `comma-separated String`!/)
   end
 
   it 'fails when `artifact_path` is an Array of something other than Strings' do