docs: add Git notes correcting recent commit messages

[Planeshifter]

Summary

This PR adds one Git note correcting a malformed trailer in a recent commit.

Notes

• 454c11ba: missing Signed-off-by — commit feat: add \blas/ext/base/swapx`(PR #12869) has noSigned-off-bytrailer, while all other GitHub-merged commits in the same batch includeSigned-off-by: Athan Reines kgryte@gmail.combetweenReviewed-byandCloses`.

Audit scope

50 commits inspected from the last 24 hours on develop (since 2026-06-15). PR-URLs and issue references were verified via the GitHub API. All other trailers, subjects, and scopes were checked against stdlib Conventional Commits style. Only the above commit was flagged.

Checklist

• Read, understood, and followed the contributing guidelines

[Planeshifter]

Closing: the premise is incorrect. 454c11ba (swapx) is not anomalous — the entire batch of commits around it (the dmaxabs-sorted rename, the ~20 ULP-migration commits, etc.) also carry no Signed-off-by trailer. The trailer was emitted consistently through ~2026-06-07 and then stops batch-wide, indicating a merge-tooling/config change rather than a per-commit omission. Backfilling Signed-off-by: Athan Reines here would make the commit inconsistent with its neighbors and assert a sign-off the current tooling no longer adds. If the dropped trailer is a concern, it's a workflow question rather than something to correct via a third-party note.

[kgryte]

@Planeshifter You should also be sure to clean up the branches when closing PRs such as this.