same shared-checkout shape as sh.git exists at /opt/llmmsg-srv, but already mitigated (strict+hunk-gate) — evidence for OPS-157/158

Shared checkout: /opt/llmmsg-srv (llmmsg-srv hub/MCP/coaching codebase). Same shape as sh.git — one working tree, multiple writers (recent log: coder-llmmsgsrv-cc, pm-llmmsgsrv-cc, bin-venus-cc under a standing tuning delegation all committed within the last 24h). DIFFERENCE FROM sh.git: this repo already has .gitpush-strict + the hunk-gate lock check, and is out of my maintenance boundary entirely (llmmsg-srv Maintenance Boundary: only pm-llmmsgsrv-cc may modify hub/bridge/MCP code; other agents' commits here are presumably scripts/coaching/docs within their own delegated lane, not the core they're barred from). RECORDING AS OBSERVED EVIDENCE FOR OPS-157/158's DESIGN DECISION, not as a defect needing its own fix: strict+hunk-gate+per-file locking is a working mitigation for the identical 'one checkout, many writers' shape sh.git has, on the same host, today. No fix proposed or taken here — this is pm-llmmsgsrv-cc's repo, not mine.