fdb9e38ad6
Add gap-preserving per-bank SlotMap (reorder + Alt-replace mutators, JSON round-trip, insertion-order migration) to bank_book; stamp captureTimeSig on Sample; pure card_meta formatters + card_drag gesture/slot module; card metadata overlay + purple selection border in the panel. Shell drop/cursor wiring deferred. Fixes: removeSample syncs SlotMap; card_drag gap-probe coordinate.