- new batch primitives: split_clips (link-preserving, single undo
command), delete_clips (gap replace + optional ripple with explicit
region support), ripple_delete_range, marker_add_ex with color
- razor/split-at-playhead, clip delete, ripple-to-point, track delete,
and the non-dialog marker path now issue facade commands instead of
the app's own undo command classes
- batch operations deliberately produce one undo command per user
action (deleting twenty clips is one entry, not twenty); selection
and transition removal stay UI-side as documented leftovers
Mike-Solar
2aa7eec016