The Worker now registers the Application layer, observability and stream tickets, validates the
container on build and ships a complete appsettings. The Gateway drops underscore fields and uses a
placeholder bucket in its default YARP transform.
Remove dead scaffold/config cruft and stale references left over from
recent refactors: dotnet's WebApi.http template file, the AppSettings
PascalCase/Dockerfile workaround (renamed to appsettings.json to match
convention), empty directories left behind by the auth-route and
folder-structure moves, a stale ESLint ignore, and the now-fully-applied
frontend refactor plan doc.