updateAndPublish
Called from render worker thread only. Reads from reader, updates back buffer, publishes as new front.
Parameters
source of the short-lived render frame.
Called from render worker thread only.
scrollbackOffset is caller-owned viewport state in lines above the live bottom viewport. The source reader clamps it before rows are copied.
Parameters
source of the short-lived render frame.
requested lines above the live bottom viewport.
Called from render worker thread only.
viewportRows requests render-only overscan rows for UI composition. It does not resize terminal state; the source reader clamps the resolved frame height before rows are copied.
Parameters
source of the short-lived render frame.
requested lines above the live bottom viewport.
requested render rows, or zero for the reader default.