fix(package): exclude CloudHypervisor README

[stephenlclarke]

Summary

Exclude Sources/CloudHypervisor/README.md from the CloudHypervisor SwiftPM target. The README remains tracked and available as source documentation, while package evaluation and builds no longer emit an unhandled-file warning.

Motivation

apple/containerization#782 added a standalone CloudHypervisor target with a README inside its source directory. SwiftPM requires non-source files in target directories to be declared as resources or excluded. This README is documentation rather than a runtime resource, so exclusion is the smallest accurate manifest change.

Changes

• Add README.md to the CloudHypervisor target's exclude list.
• Preserve the existing README content and location.
• Leave runtime code, products, resources, and package APIs unchanged.

Validation

swift package describe >/dev/null
swift test --disable-automatic-resolution --filter CloudHypervisorTests
make check
git diff --check upstream/main...HEAD

• Package evaluation completes without the Sources/CloudHypervisor/README.md warning.
• All 41 focused CloudHypervisorTests pass.
• Swift formatting and Hawkeye license checks pass.
• The committed diff has no whitespace errors.

Compatibility And Risk

This manifest-only change does not alter compiled sources, runtime resources, public APIs, or supported platforms. The README is already non-executable documentation, so excluding it accurately records SwiftPM's intended treatment of the file.

Related

• Follow-up to apple/containerization#782.

Release Note Highlight

• Stops SwiftPM builds from warning about the CloudHypervisor README added by apple/containerization#782.