fix: add options property to syndicator for Indiekit compatibility

Indiekit's endpoint-posts accesses target.options.checked directly on
syndicator objects. Upstream syndicators are class instances with
this.options from the constructor. Our plain-object syndicator lacked
this property, causing a 500 TypeError on post creation.

index.js

@@ -284,6 +284,7 @@ export default class ActivityPubEndpoint {
     const self = this;
     return {
       name: "ActivityPub syndicator",
+      options: { checked: self.options.checked },
 
       get info() {
         const hostname = self._publicationUrl

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@rmdes/indiekit-endpoint-activitypub",
-  "version": "0.1.4",
+  "version": "0.1.5",
   "description": "ActivityPub federation endpoint for Indiekit via Fedify. Adds full fediverse support: actor, inbox, outbox, followers, following, syndication, and Mastodon migration.",
   "keywords": [
     "indiekit",