See input_v1::Session::advance. Returns a { done, stageComplete, stepsTaken, loadFactor, error, recorderBatches } object — recorderBatches holds only the samples
this call produced (results-storage-indexeddb.md's recorderBatch, one entry per
recorder that recorded this call), not the whole run's history. There is no separate
"samples so far" accessor: a caller that needs the full history accumulates these
batches itself, same as the planned results-storage worker will.
The AnalysisSequence stage id advance is currently in (or, once
done, whichever stage stopped it) — undefined once every stage has
completed.
Frequencies, mode shapes and participation of every Modal stage finished so far
({ stages: ModalStageResult[] }); empty until a modal stage completes. Read it after
advance reports done, or whenever a stage has completed.
Opaque handle to a decoded, steppable analysis session — the
Sessionenum itself can't cross the boundary directly, sincewasm_bindgenrequires an exported type to be a plain struct.