APPROVE
Blockers: none.
The packet is implementable as a geometry-only cursor on parent `a96d86e28d384cdf656aadc4282c78c0c170c102` (Hemera `d5f0a095`). Verdict is from the supplied source, witnesses, and raw records only. Omitted bodies were not read, and tests were not rerun.
Scope holds. The production set is `cyber-bao/src/traversal.rs` plus one `pub mod traversal` export, with `tests/range_traversal.rs` and `tests/range_traversal_allocation.rs`. `BaoChunk`, `BlockSize`, and `TreeNode` already exist without `std`. The cursor stays allocation-free and `no_std`, takes one half-open `Range<u64>`, and leaves the eager traversals, slice wire, FSM, consumers, lock, and version untouched. Kadek row 4 is served only as the range-geometry prerequisite: empty output is specified as a geometric result, and proof parsing, particle/root association, sealed source, consumer migration, and rung/release closure stay outside the unit. Inherited no-default major-floor, red gate, and runtime-timeout attributions stay with the reducer review.
Checked geometry matches the literals and the current tree. Block size is rejected for `log > 51` before the shift; `4096_u64 << log` must then fit `usize`, so the frozen witness’s 0..=19 on 32-bit and 0..=51 on 64-bit, across all 256 `BlockSize` values, is the right admission rule. Invalid block size precedes `InvalidRange`. Admitted ranges are `start <= end` and `end <= size`; `start == end == size` emits nothing, and an empty range past EOF is `InvalidRange`. Nonempty selection is `start / group_bytes .. (end - 1) / group_bytes + 1`. `N = ceil(size / group_bytes)` is at most `2^52`. The split is the largest power of two strictly below `count`, which is Hemera’s `2^(ceil(log2 N) - 1)`. Parent index `2 * (first + left_count) - 1` stays below `2^53`. Checked small shapes agree with that rule and with today’s filtered preorder: 3, 5, 7, and 17 groups, the half-open flag rows, right-only `P7:R P11:R L6` with no node 13, and `P31:R L16`. ROOT is only the first emitted item. The `u64::MAX` log-0 right spine is `2^53 - 2^k - 1` for `k = 52..1`, then chunk `4503599627370495` of length 4095. Log 51 is `P1:R` plus the non-root leaf at chunk `2251799813685248`, length `2^63 - 1`. The left prefix is `2^k - 1` for `k = 52..1`, then leaves 0 and 1. Pop-then-push peaks at 53 stored frames on that prefix. One pop yields one item; only intersecting children are pushed. `is_complete` is true as soon as the last item is emitted, including for an admitted empty cursor. The release record’s legacy last-group length 4096 and the debug overflow panics stay attributed to the old API; the new witness pins 4095 and does not use that probe as the oracle. The external probe’s exit 101 / `E0432` shows only that `cyber_bao::traversal` is absent. Tooling supports a `thumbv7em-none-eabi` compile and no 32-bit runner, which the plan states as compilation rather than a 32-bit runtime pass.
Advice: compute `N` with overflow-safe `div_ceil` (`u64::MAX` makes `size + group_bytes - 1` wrap). Pop the current frame before the two child pushes so the 53-slot ceiling holds. Treat an admitted group width as an integer only; on 32-bit, log 19 is `2^31` and is not a valid allocation size. Link the `no_std` consumer, since `cargo check` alone does not show a missing allocator. After approval, record the in-repo parent compile failure of these same tests before any production edit.