Address workspace accounting review feedback
Add estimator-aware NHWC and CUDA budget coverage, make resource arithmetic checked, clarify per-graph Level-2 reporting, and document deferred plugin estimator parity.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Copilot-Session: 1faf9517-5062-4655-a967-3834143334d0
