What

Automate the SHA512 hash update in ports/kcenon-common-system/portfile.cmake:8 so that each new release tag updates the hash without manual editing.

• Current: SHA512 is hardcoded; every release requires a manual vcpkg install --head + hash copy
• Expected: Release workflow computes and commits the new hash automatically
• Scope: ports/kcenon-common-system/portfile.cmake, release GitHub Actions workflow

Why

• Manual hash updates are error-prone and a common cause of broken vcpkg installs
• Release cadence slows down when the hash step is forgotten
• Consistency across the kcenon-* ecosystem benefits from one shared automation pattern

How

Technical Approach

1. Add a release-portfile.yml workflow triggered on release: published
2. Download the tagged tarball, compute SHA512, patch portfile.cmake, open an auto-PR to the vcpkg registry
3. Document the new release flow in docs/RELEASE.md

Acceptance Criteria

• Release workflow computes SHA512 automatically
• Auto-generated PR in kcenon/vcpkg-registry updates REF and SHA512
• Manual-hash instructions removed from release notes template
• Tested on one patch release (e.g. v1.0.1)