Rework v2.8.0 changelog and add release notes

Editor assessment

`chore: rework v2.8.0 changelog and add release notes` states both artifacts and the release concerned; for release administration that is complete communication, and the verb `rework` honestly signals restructuring rather than a trivial edit. No scope is needed. No body details what was reworked — a minor gap — but the subject carries the essentials for a maintenance task. The trailing PR reference is clean. Imperative verb, no trailing period, tidy. Clear, correct, and self-contained: a publishable example.