Add management of webmentions

slices/admin/repos/webmention_repo.rb

@@ -0,0 +1,13 @@
+module Admin
+  module Repos
+    class WebmentionRepo < Adamantium::Repo[:webmentions]
+      commands update: :by_pk
+
+      def list_all
+        webmentions
+          .order(:id)
+          .to_a
+      end
+    end
+  end
+end