Sync slice traversal review

Fresh different-vendor Claude Opus PLAN and full CODE sessions both returned APPROVE. The code pass reviewed the final five-file patch plus surrounding tree, sync/FSM, hash and outboard code. It explicitly approved the additional test-only encoded to _encoded binding correction: call and value lifetime stay intact. The production change shares the existing filtered traversal and visited-child stack discipline. Literal independent proofs exercise the excluded-left defect, deeper/sparse/grouped/partial ranges and authentication failures.

Root read the production diff and new tests, checked each frozen source SHA256, and committed identical implementation 590e69ea0eebcea4c21320a88eed214dc5459de1. The archived source patch hash also matches a fresh Git diff of that commit. Scoped reproduction was replayed from the commit; its nonzero exit correctly retains baseline Clippy failures. Full-workspace failures and missing tools are in the receipt.

No soundness proof, complete upstream gate, Particle/root equivalence, bounded allocation, declared-size/trailing-byte strictness or grouped ROOT repair follows from this review. The reviewer supplied source reasoning and executed no gates. The generic roundtrip property and hash-helper consolidation are optional later work; neither is folded into this narrow repair. Baseline Clippy was independently reproduced; a pristine full-workspace build was not repeated.

Invocation: claude -p --model opus with source-only/no-tools system prompt, --no-session-persistence --strict-mcp-config --mcp-config '{"mcpServers":{}}' --tools '' --max-turns 2. Both sessions completed normally with explicit verdicts. Review SHA256 values are pinned in the receipt's gate index; local input/output prefix is /tmp/radio-kadek-slice-traversal-{plan,code}-{brief,review}.txt.

The review's owner-only merge footer is not an additional repository rule. The owner's ongoing implementation/review/ordinary-merge instruction remains in force; owner-only bump/tag/release/promotion/publication remains excluded. Red baseline gates require an explicit decision label and wip commits, and are never presented as automatic all-green policy acceptance or kadek phase completion.