What

Submit kcenon-common-system to the official microsoft/vcpkg registry as the first kcenon system to land upstream. This validates the port format end-to-end and unblocks future submissions for thread/logger/etc.

• Current: All 8 kcenon ports live in the kcenon-owned vcpkg-registry; zero PRs have been opened against microsoft/vcpkg (verified by gh search prs --repo microsoft/vcpkg --author kcenon)
• Expected: A merged port in microsoft/vcpkg/ports/kcenon-common-system/ with passing CI
• Scope: vcpkg port submission + small adjustments to the existing port to meet upstream requirements

Why

• This is the final unmet acceptance criterion of #646
• Upstream presence dramatically lowers the install friction — vcpkg install kcenon-common-system works without a registry-overlay configuration
• Successfully landing one port establishes the playbook for the remaining seven

Where

• New PR target: microsoft/vcpkg
• Source port: kcenon/vcpkg-registry/ports/kcenon-common-system/

How

Technical Approach

1. Read vcpkg contributing guide for current port submission rules
2. Audit the existing kcenon-common-system port for upstream-required fields:
   • description length and quality
   • homepage, license (SPDX format)
   • dependencies use upstream port names (no kcenon- prefix collisions)
3. Test locally with vcpkg --overlay-ports=... install kcenon-common-system against a fresh vcpkg checkout
4. Open PR against microsoft/vcpkg with port files
5. Address upstream review feedback (license, naming, build flags) — typically 1-3 review cycles

Acceptance Criteria

• PR opened against microsoft/vcpkg
• PR passes upstream CI (Windows/Linux/macOS triplet matrix)
• PR merged
• kcenon vcpkg-registry README updated to note upstream availability

Risks / Blockers

• Upstream may require port rename if kcenon- prefix conflicts with naming conventions
• vcpkg.json dependencies may need transitive verification — every kcenon-* dep must also be reachable upstream eventually
• Review cycle latency is fully external — track but do not block other work

Part of #646.