Add FASP follow recommendation support (#34964)

app/models/async_refresh.rb

@@ -22,6 +22,10 @@ class AsyncRefresh
     new(redis_key)
   end
 
+  def self.exists?(redis_key)
+    redis.exists?(redis_key)
+  end
+
   attr_reader :status, :result_count
 
   def initialize(redis_key)
@@ -49,6 +53,11 @@ class AsyncRefresh
     @status = 'finished'
   end
 
+  def increment_result_count(by: 1)
+    redis.hincrby(@redis_key, 'result_count', by)
+    fetch_data_from_redis
+  end
+
   def reload
     fetch_data_from_redis
     self