Merges main through #3283 (Smart Filters: distinct editors, shared
disclosure and stable alpha).
filter_dialog.rs: main's split of the preview into is_smart_edit,
smart_preview_factor and scale_preview_params is kept. The plug-in branch
from #7524 (plugin_cmds::scale_for_preview scales only declared pixel
lengths) moved into scale_preview_params, so it applies to a plug-in run
on its own and to a plug-in recorded as a smart filter.
smart_ui.rs open_editor: main's smart_filter_dialog::target flow and the
shared adjust/filter dialog opening are kept; the Liquify re-open with
recorded strokes (r4) stays ahead of it. The old per-adjustment
edit_filter call is dropped with main's rewrite.
aiongg
2496742eaa