What

Document version pins for every Tier-0/1/2 system in ECOSYSTEM_OVERVIEW.md (or a new docs/ECOSYSTEM_VERSIONS.md) so downstream consumers can lock to a known-good baseline of the kcenon stack.

• Current: ECOSYSTEM.md, ECOSYSTEM_OVERVIEW.md exist but contain no version pin information; consumers must check each repo's vcpkg.json individually
• Expected: A single table listing each system's current vcpkg port version, the kcenon vcpkg-registry baseline SHA, and any cross-system version constraints
• Scope: docs only

Why

• Closes a gap in #646 (Ecosystem-wide vcpkg distribution readiness EPIC)
• Acceptance criterion "Version pins documented in ecosystem manifest" is currently unmet — no version table exists in any ecosystem doc
• Downstream consumers cannot reproduce a known-good ecosystem composition without manually crawling each port

Where

• Modify: ECOSYSTEM_OVERVIEW.md (add "Versions" section) OR new docs/ECOSYSTEM_VERSIONS.md
• Reference data: kcenon/vcpkg-registry/ports/kcenon-*/vcpkg.json (current versions per port)

How

Technical Approach

1. Enumerate all 8 kcenon ports in vcpkg-registry: common, thread, logger, container, monitoring, database, network, pacs
2. For each port, capture: current version field, baseline registry SHA, dependency constraints (e.g., logger depends on thread x.y+)
3. Cross-reference Tier classification (Tier-0/1/2) — pin only Tier-0/1/2 in the manifest
4. Add a "Reproducing the ecosystem baseline" snippet showing the vcpkg-configuration.json that locks to the listed versions
5. Add a "How versions advance" subsection pointing to release.yml / sync-vcpkg-registry.yml as the source of truth

Acceptance Criteria

• Version table covers all Tier-0/1/2 systems
• Baseline SHA from vcpkg-registry referenced
• Reproducible vcpkg-configuration.json snippet included
• README links to the version manifest

Part of #646.