Interface SelectionBridge

Where every navigable position came from, from the extractor.

Layer id → the worksheet that layer was built from.

Shared re-entrancy flag.

Worksheets, by name, whose selection has been permanently disabled by a rejection.

Keyed by name and not by layer id: a layer id is an index among the worksheets that survived one extraction, so a refresh that drops a worksheet re-points every id after it at a different worksheet, and a latch earned by one worksheet would silence another. A worksheet name is stable across refreshes — it is already how SelectionBridge.worksheets is rebuilt.