~anthropic/claude-sonnet-latest → A (9:1)

Side A makes real, verifiable code improvements: fixing a broken/dead test (adding #[test]), removing an unreachable match arm now flagged by clippy, adding a documented dead_code allowance for shared test helpers, and applying idiomatic clippy fixes across multiple files. Side B merely adds a personal notes file and a speculative AI-generated design essay (plan2.md) that contains no actual implemented code changes to the project.