fix(grid): improve scrolling and sidebar responsiveness

apps/desktop/src/lib/dataGrid/canvasDataGridRenderer.ts

@@ -381,16 +381,14 @@ export function drawCanvasDataGrid(options: DrawCanvasDataGridOptions) {
       ctx.font = value === null ? italicFont : tabularFont;
       setCanvasNumericVariant(ctx, value === null ? "normal" : "tabular-nums");
       const textLeft = alignCanvasPixel(drawX + 12, dpr);
-      const paddedMaxWidth = Math.max(0, drawX + colWidth - textLeft - 12);
+      const cellMaxWidth = Math.max(0, colWidth - 24);
       const isEditingThisCell = editingCell?.rowId === item.id && editingCell.col === actualColIdx;
       const rawDisplayText = item.isDraft && value === null ? (draftCellPlaceholder ?? "") : formatCell(value, actualColIdx);
       const displayText = isEditingThisCell ? "" : firstLineCellDisplayValue(rawDisplayText);
-      const needsTruncation = ctx.measureText(displayText).width > paddedMaxWidth;
-      const textMaxWidth = needsTruncation ? Math.max(0, drawX + colWidth - textLeft) : paddedMaxWidth;
-      const text = isEditingThisCell ? displayText : fitCanvasText(ctx, displayText, textMaxWidth - 12);
+      const text = isEditingThisCell ? displayText : fitCanvasText(ctx, displayText, cellMaxWidth);
       ctx.fillText(text, textLeft, textY);
       if (item.isDeleted && text) {
-        const textWidth = Math.min(ctx.measureText(text).width, textMaxWidth);
+        const textWidth = ctx.measureText(text).width;
         ctx.strokeStyle = theme.foreground;
         ctx.beginPath();
         ctx.moveTo(textLeft, textY);

apps/desktop/src/lib/sidebar/sidebarPasteHandlerRegistry.ts

@@ -0,0 +1,40 @@
+export type SidebarPasteHandler = () => void;
+
+export interface SidebarPasteHandlerRegistry {
+  register: (nodeId: string, handler: SidebarPasteHandler) => () => void;
+  request: (nodeId: string) => boolean;
+}
+
+export function createSidebarPasteHandlerRegistry(): SidebarPasteHandlerRegistry {
+  const handlersByNodeId = new Map<string, Set<SidebarPasteHandler>>();
+
+  function register(nodeId: string, handler: SidebarPasteHandler) {
+    let handlers = handlersByNodeId.get(nodeId);
+    if (!handlers) {
+      handlers = new Set();
+      handlersByNodeId.set(nodeId, handlers);
+    }
+    handlers.add(handler);
+
+    return () => {
+      const currentHandlers = handlersByNodeId.get(nodeId);
+      if (!currentHandlers) return;
+      currentHandlers.delete(handler);
+      if (currentHandlers.size === 0) handlersByNodeId.delete(nodeId);
+    };
+  }
+
+  function request(nodeId: string): boolean {
+    const handlers = handlersByNodeId.get(nodeId);
+    if (!handlers?.size) return false;
+
+    // The sticky database row may duplicate a virtualized row. Prefer the most
+    // recently registered live instance while keeping older owners as fallback.
+    let activeHandler: SidebarPasteHandler | undefined;
+    for (const handler of handlers) activeHandler = handler;
+    activeHandler?.();
+    return true;
+  }
+
+  return { register, request };
+}

apps/desktop/src/lib/sidebar/sidebarTreeContext.ts

@@ -5,6 +5,7 @@ export interface SidebarTreeContext {
   getVisibleNodes: () => TreeNode[];
   getVisibleNodeIndex: (id: string) => number;
   setTableSearchQuery?: (parentNodeId: string, query: string) => void;
+  registerPasteHandler?: (nodeId: string, callback: () => void) => () => void;
 }
 
 export const sidebarTreeContextKey: InjectionKey<SidebarTreeContext> = Symbol("sidebar-tree-context");