Capture the report target and reject whole-job nesting, open progress
windows, interactive fill and busy plate actions across every view
sharing the nest; revalidate after the save dialog, capture the snapshot
synchronously on the UI thread and render it through OpenNest.Reporting.
Windows adapter tests cover enablement, guards, cancel, success and a
write failure against an existing destination (compile-only on Linux;
Windows runtime acceptance still owed).
