DnD source+destination wiring from 1cf17dc builds but the drag-drop
doesn't fire reliably in practice (suspected: either dnd_source's
shell.capture_event() on CursorMoved swallows events the destination
needs to see, or intra-window DnD has a Wayland-specific hiccup on the
current sctk/cosmic-comp pairing).
Adds two plain click-handled buttons per enabled row (↑ go-up-symbolic,
↓ go-down-symbolic, both disabled at list edges) so reorder is
functional regardless of DnD state. Backed by new messages
ToolbarMoveUp / ToolbarMoveDown that swap adjacent positions in the
Vec<ToolbarAction>.
The drag handle + DnD source/destination wrapping stays in place — if
DnD gets fixed upstream or on a future libcosmic it'll Just Work, and
the arrows remain as a keyboard-friendly fallback.
leyoda
11d435770e