chore: Limit conversation resolution Job (#6433)

We will be adding a limit to the resolution job so that it is performed at a spaced interval. This will ensure there won't be a sudden spike in resource usage

fixes: chatwoot/product#707

app/jobs/conversations/resolution_job.rb

@@ -1,8 +1,9 @@
 class Conversations::ResolutionJob < ApplicationJob
-  queue_as :medium
+  queue_as :low
 
   def perform(account:)
-    resolvable_conversations = account.conversations.resolvable(account.auto_resolve_duration)
+    # limiting the number of conversations to be resolved to avoid any performance issues
+    resolvable_conversations = account.conversations.resolvable(account.auto_resolve_duration).limit(Limits::BULK_ACTIONS_LIMIT)
     resolvable_conversations.each(&:toggle_status)
   end
 end

app/models/conversation.rb

@@ -63,7 +63,7 @@ class Conversation < ApplicationRecord
   scope :assigned, -> { where.not(assignee_id: nil) }
   scope :assigned_to, ->(agent) { where(assignee_id: agent.id) }
   scope :resolvable, lambda { |auto_resolve_duration|
-    return [] if auto_resolve_duration.to_i.zero?
+    return none if auto_resolve_duration.to_i.zero?
 
     open.where('last_activity_at < ? ', Time.now.utc - auto_resolve_duration.days)
   }