ci: migrate tests to Policyfile

[damacus]

Summary

• Replace Berkshelf test resolution with Policyfile.
• Resolve ms_dotnet from its maintained upstream repository.
• Map local and CI Kitchen suites to the Policyfile run list.
• Repair current Markdown table lint configuration.
• Generate, but do not track, the Policyfile lock.

Verification

• chef install Policyfile.rb
• Cookstyle: 0 offences
• ChefSpec: 27 examples, 0 failures
• markdownlint: 0 issues
• Kitchen configuration resolves default-windows-2019; the Windows converge requires the existing CI runner.

[github-actions]

Slowest examples

Top 10 slowest examples (1.04 seconds, 45.51% of total time)

Example	Description	Time in seconds
spec/unit/resources/powershell_wmf_spec.rb:65	powershell_wmf when installing PowerShell 5.1 on Windows Server 2008 R2 is expected to include recipe "ms_dotnet::ms_dotnet4"	0.14623
spec/unit/resources/powershell_wmf_spec.rb:114	powershell_wmf when using the legacy reboot timeout override is expected to eq 2	0.14581
spec/unit/resources/powershell_dsc_spec.rb:17	powershell_dsc is expected to install powershell_wmf "4.0"	0.12062
spec/unit/resources/powershell_wmf_spec.rb:52	powershell_wmf when installing PowerShell 4.0 with an invalid .NET requirement raises an error	0.09084
spec/unit/resources/powershell_wmf_spec.rb:78	powershell_wmf when installing PowerShell 5.1 on Windows Server 2008 R2 is expected to equal true	0.09057
spec/unit/resources/powershell_lcm_spec.rb:42	powershell_lcm with action :disable is expected to install powershell_wmf "5.1"	0.09055
spec/unit/resources/powershell_wmf_spec.rb:98	powershell_wmf when requesting a delayed reboot with an explicit delay is expected to eq 5	0.09011
spec/unit/resources/powershell_wmf_spec.rb:20	powershell_wmf when installing PowerShell 2.0 on Windows Server 2012 is expected to install windows_feature "MicrosoftWindowsPowerShellV2"	0.08896
spec/unit/resources/powershell_wmf_spec.rb:32	powershell_wmf when installing PowerShell 3.0 on Windows Server 2008 R2 is expected to include recipe "ms_dotnet::ms_dotnet4"	0.08864
spec/unit/resources/powershell_wmf_spec.rb:66	powershell_wmf when installing PowerShell 5.1 on Windows Server 2008 R2 is expected to create remote_file "D:/a/_temp/d20260816-4304-qlz4xf\wmf51.zip"	0.08858