Add drag-to-reorder for fundraising grid views

Sidebar view list is now drag-reorderable (HTML5 DnD mirroring the
column-reorder idiom: moveViewBefore + draggingViewId/dragOverViewId).
Order persists via the grid page's existing autosave (views is already
in its snapshot + deps), the same path rename/delete use; no backend
change. Render-smoke green.

frontend/index.html

@@ -190,6 +190,14 @@
             color: #fff;
         }
 
+        .sub-nav-item.view-dragging {
+            opacity: 0.55;
+        }
+
+        .sub-nav-item.view-drag-over {
+            box-shadow: inset 0 2px 0 #4a9adf;
+        }
+
         .column-header-inner {
             position: relative;
             display: flex;
@@ -11172,6 +11180,25 @@
             const [activeGridView, setActiveGridView] = useState('view-main');
             const [gridUiAction, setGridUiAction] = useState(null);
             const [sidebarContextMenu, setSidebarContextMenu] = useState(null);
+            const [draggingViewId, setDraggingViewId] = useState(null);
+            const [dragOverViewId, setDragOverViewId] = useState(null);
+
+            // Drag-reorder the saved grid views in the sidebar. Mirrors moveColumnBefore:
+            // mutate gridViews only — the grid page's autosave (which has `views` in its
+            // snapshot + deps) persists the new order to /api/fundraising/state, same path
+            // rename/delete already use.
+            const moveViewBefore = (fromId, targetId) => {
+                if (!fromId || !targetId || fromId === targetId) return;
+                setGridViews((prev) => {
+                    const fromIndex = prev.findIndex((v) => v.id === fromId);
+                    const targetIndex = prev.findIndex((v) => v.id === targetId);
+                    if (fromIndex < 0 || targetIndex < 0 || fromIndex === targetIndex) return prev;
+                    const next = [...prev];
+                    const [moved] = next.splice(fromIndex, 1);
+                    next.splice(targetIndex, 0, moved);
+                    return next;
+                });
+            };
 
             useEffect(() => {
                 localStorage.setItem(GRID_VIEW_STORAGE_KEY, JSON.stringify(gridViews));
@@ -11308,12 +11335,38 @@
                                 {gridViews.map((v) => (
                                     <button
                                         key={v.id}
-                                        className={`sub-nav-item ${activeGridView === v.id ? 'active' : ''}`}
+                                        className={`sub-nav-item ${activeGridView === v.id ? 'active' : ''} ${draggingViewId === v.id ? 'view-dragging' : ''} ${dragOverViewId === v.id ? 'view-drag-over' : ''}`.trim()}
+                                        draggable={true}
                                         onClick={() => {
                                             setPage('fundraising-grid');
                                             setActiveGridView(v.id);
                                         }}
                                         onContextMenu={(e) => openSidebarContextMenu(e, { kind: 'view', viewId: v.id })}
+                                        onDragStart={(e) => {
+                                            setDraggingViewId(v.id);
+                                            e.dataTransfer.effectAllowed = 'move';
+                                            e.dataTransfer.setData('text/plain', v.id);
+                                        }}
+                                        onDragOver={(e) => {
+                                            e.preventDefault();
+                                            if (!draggingViewId || draggingViewId === v.id) return;
+                                            setDragOverViewId(v.id);
+                                            e.dataTransfer.dropEffect = 'move';
+                                        }}
+                                        onDragLeave={() => {
+                                            setDragOverViewId((cur) => (cur === v.id ? null : cur));
+                                        }}
+                                        onDrop={(e) => {
+                                            e.preventDefault();
+                                            const droppedId = e.dataTransfer.getData('text/plain') || draggingViewId;
+                                            moveViewBefore(droppedId, v.id);
+                                            setDragOverViewId(null);
+                                            setDraggingViewId(null);
+                                        }}
+                                        onDragEnd={() => {
+                                            setDragOverViewId(null);
+                                            setDraggingViewId(null);
+                                        }}
                                     >
                                         • {v.name}
                                     </button>