Summary

Add a dedicated CI workflow (ecosystem-vcpkg-integration.yml) and minimal consumer projects that validate the full kcenon ecosystem dependency graph — from common_system (Layer 0) through pacs_system (Layer 7) — via vcpkg registry consumption.

• New workflow: 8 layer-ordered jobs with needs: chains that model the actual dependency DAG
• Consumer projects: 8 minimal C++ consumers under tests/ecosystem-consumer/, one per port
• Shared config: Single vcpkg-configuration.json pointing to kcenon/vcpkg-registry
• Error reporting: ::error:: annotations and failure artifact upload for fast debugging

Dependency Graph (Job DAG)

Layer 0: common_system
  ├─ Layer 1: thread_system
  │    ├─ Layer 2: logger_system ──┐
  │    └─ Layer 4: network_system ─┤
  ├─ Layer 3: container_system ────┤
  └─ Layer 5: database_system ─────┤
                                   ├─ Layer 6: monitoring_system
                                   └─ Layer 7: pacs_system

Layers 2/3/4/5 run concurrently where dependencies allow. Total sequential depth is ~4 layers, not 8.

Design Decisions

Registry consumption vs overlay-ports: The issue (#604) references overlay-ports, but this implementation uses vcpkg manifest mode with vcpkg-configuration.json pointing to kcenon/vcpkg-registry. This is intentional — the registry path is what real downstream consumers use, so it validates the actual consumption experience including version resolution and baseline constraints. All 8 ports are registered in the ecosystem's vcpkg-registry.

fail-fast strategy: fail-fast: false within each job's OS matrix (so both ubuntu and macOS complete independently), with layer-level gating via needs: chains (if Layer 0 fails on both runners, Layer 1+ won't start).

Review Summary

Two review rounds completed. All findings resolved:

Deferred Items

• Consumer projects currently validate find_package + link + run, but only common-system tests actual library functionality (creates a Result<int>). Other consumers include a header and link but don't instantiate types. Can be strengthened in a follow-up.
• Layer numbering is 0-indexed in implementation vs 1-8 in the issue text. Job names are descriptive regardless.

Files Changed

• .github/workflows/ecosystem-vcpkg-integration.yml — 8-job workflow (609 lines)
• tests/ecosystem-consumer/vcpkg-configuration.json — shared registry config
• tests/ecosystem-consumer/<port>/CMakeLists.txt — per-port CMake (8 files)
• tests/ecosystem-consumer/<port>/main.cpp — per-port consumer (8 files)
• tests/ecosystem-consumer/<port>/vcpkg.json — per-port manifest (8 files)

Test plan

• Workflow YAML passes GitHub Actions syntax validation
• workflow_dispatch trigger allows manual test run
• Layer 0 (common_system) installs and consumer builds on ubuntu-24.04 and macos-14
• Layer dependency chain gates correctly (Layer 1+ waits for Layer 0)
• Failure in any layer produces ::error:: annotation in GitHub Actions UI
• Failure artifacts are uploaded with vcpkg install logs
• Nightly schedule triggers at 03:00 UTC on main branch

Closes #604