The import review grid rendered every parsed row and re-scanned all rows three
times per render for its counts; RawCsvReviewView recomputes rows + counts once
per change and the grid renders through Virtualize. The export modal embedded the
whole CSV twice (textarea + base64 data: URI); it now shows a 50-line preview
and links to GET /api/raw/tags.csv (ConfigEditor, like /raw), which runs the same
RawTagCsvExport builder and sends it as an attachment.
Refs #745
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
M1: PageErrorBoundary wraps the body of every InteractiveServer page; the inert layout boundary is removed.
m1: DisposeBridge cancels its CTS when the 5 s wait times out.
m2: a CSV import that commits after the modal closed still raises OnSaved.
m3: document SecurityMode=None no-fallback in Client.CLI.md / Client.UI.md.
m4: browsePageDelayMs written only when loaded or changed; negative flagged.
Claude-Session: https://claude.ai/code/session_01Ef2ozxS7QPanGT8uoATbTe
Joseph Doherty