changelog.d/ — the next release's section, one fragment per issue
Machine-assembled by bin/changelog-assemble (#112): every PR that changes
behavior writes one file here — <issue>.md, the exact prose that will be
published, nothing else — and the release PR folds them all into the next
## X.Y.Z — DATE section of CHANGELOG.md, consuming them. Distinct
filenames never conflict, which is this directory's whole reason to exist.
This README is the marker that keeps the directory tracked when it holds no
fragments (#112 D1) — changelog-armed refuses a tree without it; do not
delete it. The shape sentinel beside it declares the set's shape —
grouped here, so every fragment carries ### headings (#182).
