react-legacy-reviewlisted

## How to use this skill 1. Identify which categories the diff touches, then read only the matching sections of `references/checklist.md` and `references/saga-patterns.md` - there is no need to read the whole catalog for a small diff. 2. Apply every rule whose category matches something the diff changes. Report each violation as a finding using the output contract below. 3. Before proposing any hook, component, or API that looks like current React advice, check it against `references/legacy-constraints.md`. Most material published in the last few years assumes React 18's concurrent renderer or a server framework; neither exists in this codebase. 4. When a finding should be deferred rather than fixed inline, record it as accepted-by-context using the policy and the one-line justification format in `references/severity.md`, not by silently skipping it. ## Categories - **RL-RENDER** - component identity, render cost, and list key stability. - **RL-EFFECT** - effect scope, dependency correctness, and cleanup. - **RL-SAGA** - generator concurrency, cancellation, and saga lifecycle. - **RL-STATE** - Redux store shape, selector cost, and serializability. - **RL-BUNDLE** - what ships in the initial download. - **RL-DOM** - direct DOM cost: list size, listener count, layout thrash. - **RL-JS** - plain JavaScript cost on a hot path, independent of React. - **RL-COMPAT** - APIs and assumptions this React version does not support. ## Output contract Report ea