feat: Introduce the crm_v2 feature flag for CRM changes (#12014)

Introduce crm_v2 feature flag for our upcoming optimisations for CRM

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Co-authored-by: Sojan Jose <sojan@pepalo.com>

app/services/search_service.rb

@@ -95,7 +95,9 @@ class SearchService
     @contacts = current_account.contacts.where(
       "name ILIKE :search OR email ILIKE :search OR phone_number
       ILIKE :search OR identifier ILIKE :search", search: "%#{search_query}%"
-    ).resolved_contacts.order_on_last_activity_at('desc').page(params[:page]).per(15)
+    ).resolved_contacts(
+      use_crm_v2: current_account.feature_enabled?('crm_v2')
+    ).order_on_last_activity_at('desc').page(params[:page]).per(15)
   end
 
   def filter_articles