SELF-REVIEW — no instructor grade/certificate
Pass each criterion only with observable evidence:
[ ] Original four-row fixture preserved: count4,total40000,web27000,store13000.
[ ] Fifth-order fixture separate: count5,total42000,web27000,store15000.
[ ] Duplicate/boolean/unknown channel refused; original data unchanged after rejection.
[ ] Separate ledger instances do not share mutable state.
[ ] Complexity explanation counts operations and states memory/average-case assumptions.
[ ] CLI success/failure stdout,stderr,exit status documented.
[ ] Real loopback HTTP valid/invalid cases tested; server closed; no public exposure.
[ ] Source package/venv distinguished from distribution/security isolation.
[ ] Local checks recorded; hosted CI/Linux/cloud claims only if separately executed.
[ ] README credits teaching code, explains own contribution and known limitations.
If any item fails, describe repair or mark unexecuted. Never invent test evidence.
