Re: [PATCH v5 00/10] commit-reach: terminate merge-base walk when one side is exhausted

> Changes since v4:
>
>  * New patch 2/10: added test_trace2_data_singular helper to
>    test-lib-functions.sh. Shows expected/actual values on assertion failure
>    instead of a silent grep failure. Makes iterating on step counts much
>    easier.
>
>  * New patch 6/10: added clock-skew topologies (se-, se2-) that expose
>    side-exhaustion bugs when the commit-date ordering fallback fires with a
>    v1 commit graph. All topologies use a shared skew_commit helper. Includes
>    step count assertions for edge-case tests from patch 3.
>
>  * Folded the nonstale_queue dedup wrapper removal (previously separate
>    patch 6/8) into the paint_state introduction in patch 7/10.
>
>  * New patch 10/10: remove the commit-date ordering fallback in
>    paint_down_to_common(). The fallback (091cf18e) was a performance
>    optimization for v1 commit graphs, but it breaks the generation ordering
>    invariant that both the side-exhaustion and single-result optimizations
>    depend on. With side-exhaustion in place, the fallback is no longer
>    needed. If kept, this supersedes the separate "commit-reach: fix
>    !FIND_ALL early exit with v1 commit graph" topic.