Context

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

Problem

• no dedicated fuzz/ target (lockfree data structures have high fuzzing value)
• measured line coverage ~41%, below the infrastructure maturity

Acceptance Criteria

• dedicated fuzz/ harness + seed corpus + weekly fuzzing workflow
• coverage raised per the 40->50->60% phased plan with codecov floor bumped accordingly

Notes

Weekly fuzzing workflow touches .github/workflows/ -> requires workflow token scope.

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.