fix(grid): avoid repeated search text allocations

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

@@ -25,6 +25,13 @@ export interface CanvasEditingCell {
   col: number;
 }
 
+/** 搜索匹配的数值 key：列头匹配 displayRow 为 -1。相比字符串拼接 key，
+ * 每次按键构建 matchSet、每帧对可见单元格查询都零字符串分配。
+ * ponytail: 列数上限 65536，网格列数远达不到 */
+export function dataGridSearchMatchKey(displayRow: number, col: number): number {
+  return (displayRow + 1) * 65536 + col;
+}
+
 export interface CanvasSearchMatch {
   kind: "cell" | "column";
   displayRow: number;
@@ -50,7 +57,7 @@ export interface DrawCanvasDataGridOptions {
   hoverCell: CanvasHoverCell | null;
   isScrolling: boolean;
   editingCell: CanvasEditingCell | null;
-  searchMatchKeys: ReadonlySet<string>;
+  searchMatchKeys: ReadonlySet<number>;
   currentSearchMatch: CanvasSearchMatch | null;
   formatCell: (value: CellValue, columnIndex: number) => string;
   draftCellPlaceholder?: string;
@@ -334,7 +341,7 @@ export function drawCanvasDataGrid(options: DrawCanvasDataGridOptions) {
       const isDirtyCell = item.isDirtyCol[actualColIdx];
       const selectedFillVisual = rowSelectionVisual || selectedCell;
       const selectedBorderVisual = rowSelectionVisual || selectedCell;
-      const isSearchMatch = paintSearchMatches && searchMatchKeys.has(`cell:${item.displayIndex}:${actualColIdx}`);
+      const isSearchMatch = paintSearchMatches && searchMatchKeys.has(dataGridSearchMatchKey(item.displayIndex, actualColIdx));
       const isCurrentSearchMatch = paintSearchMatches && currentSearchMatch?.displayRow === item.displayIndex && currentSearchMatch.col === actualColIdx;
       const clippedX = Math.max(drawX, rowNumberWidth);
       const cellPaintWidth = Math.min(width, drawX + colWidth) - clippedX;

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

@@ -0,0 +1,38 @@
+import type { CellValue } from "@/lib/dataGrid/cellValue";
+
+type RowLowerTextEntry = {
+  /** 每列缓存时的源值引用：单元格被原地编辑后引用不再相等，仅重算该格 */
+  values: CellValue[];
+  lowers: (string | undefined)[];
+};
+
+/**
+ * 搜索用小写文本缓存，按行数组身份挂 WeakMap：
+ * - 工作集天然等于当前在内存中的结果行（行数组是 markRaw 的稳定引用），
+ *   不存在固定容量 LRU 在全量顺序扫描下的零命中抖动，GC 自动回收旧结果；
+ * - 展示格式化器/列类型变化时由调用方 clear() 整体失效。
+ */
+export function createRowLowerTextCache(format: (value: CellValue, columnIndex: number) => string) {
+  let cache = new WeakMap<object, RowLowerTextEntry>();
+
+  function get(rowData: CellValue[], columnIndex: number): string {
+    let entry = cache.get(rowData);
+    if (!entry) {
+      entry = { values: [], lowers: [] };
+      cache.set(rowData, entry);
+    }
+    const value = rowData[columnIndex];
+    const cached = entry.lowers[columnIndex];
+    if (cached !== undefined && Object.is(entry.values[columnIndex], value)) return cached;
+    const lower = format(value, columnIndex).toLowerCase();
+    entry.values[columnIndex] = value;
+    entry.lowers[columnIndex] = lower;
+    return lower;
+  }
+
+  function clear() {
+    cache = new WeakMap<object, RowLowerTextEntry>();
+  }
+
+  return { get, clear };
+}