Add Duo Chat GA alert

app/assets/javascripts/persistent_user_callouts.js

app/models/users/callout.rb

app/views/groups/show.html.haml

app/views/projects/empty.html.haml

app/views/projects/show.html.haml

config/feature_flags/gitlab_com_derisk/duo_chat_ga_alert.yml

doc/api/graphql/reference/index.md

...scripts/ai/components/global_callout/duo_chat_callout.vue

ee/app/assets/javascripts/ai/tanuki_bot/index.js

ee/app/helpers/ee/users/callouts_helper.rb

ee/app/views/projects/_duo_chat_ga_alert.html.haml

ee/app/views/shared/_duo_chat_ga_alert.html.haml

ee/spec/features/duo_chat_ga_alert_spec.rb

...end/ai/components/global_callout/duo_chat_callout_spec.js

ee/spec/helpers/ee/users/callouts_helper_spec.rb

ee/spec/views/groups/show.html.haml_spec.rb

ee/spec/views/projects/_duo_chat_ga_alert.html.haml_spec.rb

ee/spec/views/projects/empty.html.haml_spec.rb

ee/spec/views/projects/show.html.haml_spec.rb

ee/spec/views/shared/_duo_chat_ga_alert.html.haml_spec.rb