Make followers/following collections public (paginated format)

Mastodon requires OrderedCollection with a `first` page link to
consider the collection public. Without it, it shows "This user
has chosen to not make this information available."

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

bp/actors/routes.py

@@ -353,13 +353,28 @@ def register(url_prefix="/users"):
             abort(404)
 
         domain = _domain()
+        collection_id = f"https://{domain}/users/{username}/followers"
         follower_list = await services.federation.get_followers(g.s, username)
+        page_param = request.args.get("page")
+
+        if not page_param:
+            return Response(
+                response=json.dumps({
+                    "@context": "https://www.w3.org/ns/activitystreams",
+                    "type": "OrderedCollection",
+                    "id": collection_id,
+                    "totalItems": len(follower_list),
+                    "first": f"{collection_id}?page=1",
+                }),
+                content_type=AP_CONTENT_TYPE,
+            )
 
         return Response(
             response=json.dumps({
                 "@context": "https://www.w3.org/ns/activitystreams",
-                "type": "OrderedCollection",
+                "type": "OrderedCollectionPage",
-                "id": f"https://{domain}/users/{username}/followers",
+                "id": f"{collection_id}?page=1",
+                "partOf": collection_id,
                 "totalItems": len(follower_list),
                 "orderedItems": [f.follower_actor_url for f in follower_list],
             }),
@@ -373,11 +388,27 @@ def register(url_prefix="/users"):
             abort(404)
 
         domain = _domain()
+        collection_id = f"https://{domain}/users/{username}/following"
+        page_param = request.args.get("page")
+
+        if not page_param:
+            return Response(
+                response=json.dumps({
+                    "@context": "https://www.w3.org/ns/activitystreams",
+                    "type": "OrderedCollection",
+                    "id": collection_id,
+                    "totalItems": 0,
+                    "first": f"{collection_id}?page=1",
+                }),
+                content_type=AP_CONTENT_TYPE,
+            )
+
         return Response(
             response=json.dumps({
                 "@context": "https://www.w3.org/ns/activitystreams",
-                "type": "OrderedCollection",
+                "type": "OrderedCollectionPage",
-                "id": f"https://{domain}/users/{username}/following",
+                "id": f"{collection_id}?page=1",
+                "partOf": collection_id,
                 "totalItems": 0,
                 "orderedItems": [],
             }),