Context

Part of kcenon/common_system#685 (Wave 1, P0). Documentation reference: common_system.

Problem (P0)

Root CHANGELOG.md (2.5KB) vs docs/CHANGELOG.md (44.9KB), plus duplicated README/CONTRIBUTING/SECURITY between root and docs/ -> change-history SSOT ambiguous.

Acceptance Criteria

• one SSOT chosen per governance doc; the other becomes a redirect stub with a marker
• open items in docs/KNOWN_ISSUES / ARCHITECTURE_ISSUES promoted to tracked GitHub issues

Derived from the 2026-05-30 multi-agent cross-system level-matching analysis (workflow wf_0a968699-e07). Reference systems: documentation=common_system, code-structure=monitoring_system, tests/examples=container_system.