yoda: direct drag-drop reorder on the toolbar itself

User feedback: going through Settings to reorder is too indirect. Now
each toolbar button is wrapped in dnd_source + dnd_destination so the
user can grab an icon in the live toolbar and drop it onto another
icon to reorder in-place. The underlying icon button keeps firing its
on_press for quick clicks (dnd_source only starts a drag past the
default 8 px motion threshold), so regular clicks continue to run the
associated Action — no mode-switch needed.

Settings retains the ↑↓/add/remove UI as a fallback (discoverability
+ keyboard-friendly) and for the same drag-drop if the user prefers
working from the panel. The config model (Vec<ToolbarAction> +
ToolbarReorder message) is already shared, so both paths mutate the
same state.

src/app.rs

@@ -6807,25 +6807,44 @@ impl Application for App {
 
         // Yoda phase 3: Dolphin-style quick actions toolbar. Items are
         // rendered from self.config.toolbar (Vec<ToolbarAction>) — the user
-        // picks the set AND the order via drag-drop in Settings. Dispatch
+        // picks the set AND the order via direct drag-drop on the toolbar.
-        // goes through Action::message so keybinding and toolbar share the
+        // Short click = action (shared Action::message dispatch); drag past
-        // same code path.
+        // the default 8px threshold = reorder (ToolbarReorder message).
         if !self.config.toolbar.is_empty() {
+            use cosmic::iced::clipboard::dnd::DndAction as DndAct;
             let clipboard_has = self.clipboard_has_content();
             let buttons: Vec<Element<_>> = self
                 .config
                 .toolbar
                 .iter()
                 .map(|a| {
-                    let (icon, label, msg) = toolbar_action_ui(*a);
+                    let action = *a;
-                    let enabled = !matches!(a, ToolbarAction::Paste) || clipboard_has;
+                    let (icon, label, msg) = toolbar_action_ui(action);
+                    let enabled = !matches!(action, ToolbarAction::Paste) || clipboard_has;
                     let btn = widget::button::icon(widget::icon::from_name(icon).size(16));
                     let btn = if enabled { btn.on_press(msg) } else { btn };
-                    widget::tooltip(
+                    let tooltip = widget::tooltip(
                         btn,
                         widget::text::body(label),
                         widget::tooltip::Position::Bottom,
+                    );
+                    let source = widget::dnd_source::<Message, ToolbarActionPayload>(tooltip)
+                        .drag_content(move || ToolbarActionPayload(action.to_u8()));
+                    widget::dnd_destination(
+                        source,
+                        vec![std::borrow::Cow::Borrowed(TOOLBAR_MIME)],
                     )
+                    .data_received_for::<ToolbarActionPayload>(
+                        move |payload: Option<ToolbarActionPayload>| {
+                            match payload.and_then(|p| ToolbarAction::from_u8(p.0)) {
+                                Some(src) if src != action => {
+                                    Message::ToolbarReorder { src, target: action }
+                                }
+                                _ => Message::ToolbarReorder { src: action, target: action },
+                            }
+                        },
+                    )
+                    .action(DndAct::Move)
                     .into()
                 })
                 .collect();