Lists (#5703)

* Add structure for lists

* Add list timeline streaming API

* Add list APIs, bind list-account relation to follow relation

* Add API for adding/removing accounts from lists

* Add pagination to lists API

* Add pagination to list accounts API

* Adjust scopes for new APIs

- Creating and modifying lists merely requires "write" scope
- Fetching information about lists merely requires "read" scope

* Add test for wrong user context on list timeline

* Clean up tests

app/models/feed.rb

@@ -1,36 +1,27 @@
 # frozen_string_literal: true
 
 class Feed
-  def initialize(type, account)
-    @type    = type
-    @account = account
+  def initialize(type, id)
+    @type = type
+    @id   = id
   end
 
   def get(limit, max_id = nil, since_id = nil)
-    if redis.exists("account:#{@account.id}:regeneration")
-      from_database(limit, max_id, since_id)
-    else
-      from_redis(limit, max_id, since_id)
-    end
+    from_redis(limit, max_id, since_id)
   end
 
-  private
+  protected
 
   def from_redis(limit, max_id, since_id)
     max_id     = '+inf' if max_id.blank?
     since_id   = '-inf' if since_id.blank?
     unhydrated = redis.zrevrangebyscore(key, "(#{max_id}", "(#{since_id}", limit: [0, limit], with_scores: true).map(&:first).map(&:to_i)
+
     Status.where(id: unhydrated).cache_ids
   end
 
-  def from_database(limit, max_id, since_id)
-    Status.as_home_timeline(@account)
-          .paginate_by_max_id(limit, max_id, since_id)
-          .reject { |status| FeedManager.instance.filter?(:home, status, @account.id) }
-  end
-
   def key
-    FeedManager.instance.key(@type, @account.id)
+    FeedManager.instance.key(@type, @id)
   end
 
   def redis