Write step-aerobics choreography as text. Each count compiles to an explicit state — where both feet are, which way each one points, on the bench or the floor, bearing weight or not — and renders as a top-down frame.
Click a move to append it to the pattern. Entry and exit states are derived by running each move, not declared — keeps lead / swaps lead comes from whether the last foot down takes weight. approx marks geometry that is a reasonable reading of the standard move and is worth a human check.
This is the archival format — one record per count, with absolute beat position, both feet, and body facing.
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