feat(perf): Cache labels on the conversation model (#8527)

app/controllers/api/v1/accounts/conversations/assignments_controller.rb

@@ -14,7 +14,8 @@ class Api::V1::Accounts::Conversations::AssignmentsController < Api::V1::Account
 
   def set_agent
     @agent = Current.account.users.find_by(id: params[:assignee_id])
-    @conversation.update_assignee(@agent)
+    @conversation.assignee = @agent
+    @conversation.save!
     render_agent
   end
 

app/controllers/api/v1/accounts/conversations_controller.rb

@@ -110,8 +110,8 @@ class Api::V1::Accounts::ConversationsController < Api::V1::Accounts::BaseContro
   end
 
   def assign_conversation
-    @agent = Current.account.users.find(current_user.id)
-    @conversation.update_assignee(@agent)
+    @conversation.assignee = current_user
+    @conversation.save!
   end
 
   def conversation