feat!: migrate yum-fedora to custom resources

[damacus]

Summary

• Remove legacy recipe and attribute API
• Add Fedora repository custom resources, docs, migration guide, and platform evidence
• Modernize ChefSpec, InSpec, Kitchen, and CI

Verification

• berks install
• cookstyle: 15 files inspected, no offenses
• chef exec rspec --format documentation: 32 examples, 0 failures
• kitchen test default-fedora-latest: idempotent second converge, InSpec passed

[github-actions]

Slowest examples

Top 10 slowest examples (0.49 seconds, 45.12% of total time)

Example	Description	Time in seconds
spec/unit/resources/yum_fedora_repositories_spec.rb:45	yum_fedora_repositories with all optional repositories managed and enabled is expected to create yum_fedora_repository "fedora-source"	0.14155
spec/unit/resources/yum_fedora_repositories_spec.rb:45	yum_fedora_repositories with all optional repositories managed and enabled is expected to create yum_fedora_repository "fedora"	0.0438
spec/unit/resources/yum_fedora_repositories_spec.rb:14	yum_fedora_repositories with default properties is expected to delete file "/etc/yum.repos.d/fedora-updates.repo"	0.04378
spec/unit/resources/yum_fedora_repositories_spec.rb:67	yum_fedora_repositories with action remove is expected to remove yum_fedora_repository "fedora-source"	0.04336
spec/unit/resources/yum_fedora_repository_spec.rb:14	yum_fedora_repository with the default fedora repository is expected to create yum_repository "fedora"	0.04309
spec/unit/resources/yum_fedora_repositories_spec.rb:16	yum_fedora_repositories with default properties is expected to create yum_fedora_repository "fedora"	0.03792
spec/unit/resources/yum_fedora_repositories_spec.rb:17	yum_fedora_repositories with default properties is expected to create yum_fedora_repository "updates"	0.03557
spec/unit/resources/yum_fedora_repositories_spec.rb:45	yum_fedora_repositories with all optional repositories managed and enabled is expected to create yum_fedora_repository "updates"	0.03527
spec/unit/resources/yum_fedora_repositories_spec.rb:67	yum_fedora_repositories with action remove is expected to remove yum_fedora_repository "updates"	0.03429
spec/unit/resources/yum_fedora_repositories_spec.rb:45	yum_fedora_repositories with all optional repositories managed and enabled is expected to create yum_fedora_repository "updates-testing"	0.03336