Single project description punctuation edit, NO PUBLISH. Read actual current metadata description/Description property. Preserve all text. If last character is '.', unchanged; otherwise trim trailing whitespace and append exactly one period. Only description mutation; no other metadata/design/sharing/datasheet/MPN edits, no docs, no publish, no child threads. Verify saved readback. Report canonical URL, exact before/after, changed/already correct/failed, readback result and zero publish calls.