fix: migrate dependency resolution to Policyfile

[damacus]

Summary

• migrate dependency resolution from Berksfile to Policyfile
• update ChefSpec setup to use Policyfile resolution
• update CI/Copilot workflow references to current sous-chefs workflow/action versions
• move cookbook limitations into AGENTS.md where present

Verification

• chef install Policyfile.rb
• cookstyle
• /opt/chef-workstation/embedded/bin/rspec --format progress
• kitchen list

[github-actions]

Slowest examples

Top 10 slowest examples (1.08 seconds, 27.7% of total time)

Example	Description	Time in seconds
spec/test/installation_package_spec.rb:159	test::installation_package Oracle 7: testing default action, default properties is expected to create yum_repository "docker"	0.15291
spec/test/container_spec.rb:957	test::container testing GPU support creates a container with GPU support	0.14755
spec/libraries/container_spec.rb:72	docker_container creates a docker container with default options is expected to create docker_container "hello_world"	0.12479
spec/libraries/container_spec.rb:471	docker_container creates a docker container with GPU support configures nvidia GPU support	0.12076
spec/test/installation_package_spec.rb:106	test::installation_package RHEL (s390x): testing default action, default properties is expected to create yum_repository "docker"	0.10828
spec/test/installation_package_spec.rb:103	test::installation_package RHEL (s390x): testing default action, default properties installs docker	0.1006
spec/libraries/container_networks_spec.rb:28	docker_container gets ip_address_from_container_networks when docker API < 1.21 gets ip_address as nil	0.09373
spec/test/service_spec.rb:75	test::service creates docker_service[default]	0.08081
spec/test/service_spec.rb:187	test::service containerd does not exist creates docker_service[default]	0.07562
spec/test/container_spec.rb:733	test::container runs execute[change_network_mode]	0.07494