Add the 8.2.0 changelog entry and align the release-facing user docs
with the current maintenance sweep so the release workflow has the
required notes and public version references in place.
Refresh README release messaging and contributor acknowledgements ahead
of the automated release commit and tag creation.
Consolidate the repository into clearer apps, tools, and layered docs areas so contributors can navigate and maintain it more reliably. Align validation, metadata sync, and CI around the same canonical workflow to reduce drift across local checks and GitHub Actions.
