Scaffold Observability Logs feature (backend)

config/feature_flags/wip/observability_logs.yml

ee/app/controllers/projects/logs_controller.rb

ee/app/helpers/projects/observability_helper.rb

ee/app/models/gitlab_subscriptions/features.rb

ee/app/policies/ee/project_policy.rb

ee/app/views/projects/logs/index.html.haml

ee/config/routes/project.rb

ee/lib/ee/gitlab/observability.rb

ee/lib/ee/sidebars/projects/menus/monitor_menu.rb

ee/spec/helpers/projects/observability_helper_spec.rb

ee/spec/lib/ee/gitlab/observability_spec.rb

ee/spec/lib/ee/sidebars/projects/menus/monitor_menu_spec.rb

ee/spec/policies/project_policy_spec.rb

ee/spec/requests/projects/logs_controller_spec.rb

ee/spec/requests/projects/metrics_controller_spec.rb

ee/spec/requests/projects/tracing_controller_spec.rb

lib/sidebars/projects/super_sidebar_menus/monitor_menu.rb

...idebars/projects/super_sidebar_menus/monitor_menu_spec.rb

spec/support/helpers/user_with_namespace_shim.yml