Move up to 100 cards to a column in one transaction

Without targetProjectId, sweeps the cards to a column on their own board - every id must belong to the same board (400 otherwise). With targetProjectId, moves the batch to that board instead (same workspace only, mirroring the single-card move). Moved cards append to the end of the target column in request order. Within-board column changes are recorded to each card's activity log. All-or-nothing; no notification emails.