feat: allow zap on linux

Library/Homebrew/cask/artifact/abstract_uninstall.rb

@@ -411,7 +411,7 @@ module Cask
             next
           end
 
-          if MacOS.undeletable?(resolved_path)
+          if undeletable?(resolved_path)
             opoo "Skipping #{Formatter.identifier(action)} for undeletable path '#{path}'."
             next
           end
@@ -538,6 +538,10 @@ module Cask
           recursive_rmdir(*resolved_paths, **kwargs)
         end
       end
+
+      def undeletable?(target); end
     end
   end
 end
+
+require "extend/os/cask/artifact/abstract_uninstall"

Library/Homebrew/extend/os/cask/artifact/abstract_uninstall.rb

@@ -0,0 +1,5 @@
+# typed: strict
+# frozen_string_literal: true
+
+require "extend/os/mac/cask/artifact/abstract_uninstall" if OS.mac?
+require "extend/os/linux/cask/artifact/abstract_uninstall" if OS.linux?

Library/Homebrew/extend/os/linux/cask/artifact/abstract_uninstall.rb

@@ -0,0 +1,23 @@
+# typed: strict
+# frozen_string_literal: true
+
+module OS
+  module Linux
+    module Cask
+      module Artifact
+        module AbstractUninstall
+          extend T::Helpers
+
+          requires_ancestor { ::Cask::Artifact::AbstractUninstall }
+
+          sig { params(target: Pathname).returns(T::Boolean) }
+          def undeletable?(target)
+            !target.parent.writable?
+          end
+        end
+      end
+    end
+  end
+end
+
+Cask::Artifact::AbstractUninstall.prepend(OS::Linux::Cask::Artifact::AbstractUninstall)

Library/Homebrew/extend/os/mac/cask/artifact/abstract_uninstall.rb

@@ -0,0 +1,25 @@
+# typed: strict
+# frozen_string_literal: true
+
+require "cask/macos"
+
+module OS
+  module Mac
+    module Cask
+      module Artifact
+        module AbstractUninstall
+          extend T::Helpers
+
+          requires_ancestor { ::Cask::Artifact::AbstractUninstall }
+
+          sig { params(target: Pathname).returns(T::Boolean) }
+          def undeletable?(target)
+            MacOS.undeletable?(target)
+          end
+        end
+      end
+    end
+  end
+end
+
+Cask::Artifact::AbstractUninstall.prepend(OS::Mac::Cask::Artifact::AbstractUninstall)