feat(dees-table): add configurable cell flash comparison and border highlight mode

ts_web/elements/00group-dataview/dees-table/dees-table.ts

@@ -695,6 +695,7 @@ export class DeesTable<T> extends DeesElement {
                               this.__editingCell?.rowId === rowId &&
                               this.__editingCell?.colKey === editKey;
                             const isFlashing = !!flashSet?.has(editKey);
+                            const useFlashBorder = isFlashing && !!col.flashBorder;
                             const cellClasses = [
                               isEditable ? 'editable' : '',
                               isFocused && !isEditing ? 'focused' : '',
@@ -702,8 +703,13 @@ export class DeesTable<T> extends DeesElement {
                             ]
                               .filter(Boolean)
                               .join(' ');
+                            const flashClass = isFlashing
+                              ? useFlashBorder
+                                ? 'innerCellContainer flashing-border'
+                                : 'innerCellContainer flashing'
+                              : 'innerCellContainer';
                             const innerHtml = html`<div
-                              class=${isFlashing ? 'innerCellContainer flashing' : 'innerCellContainer'}
+                              class=${flashClass}
                             >
                               ${isEditing ? this.renderCellEditor(itemArg, col) : content}
                             </div>`;
@@ -1362,6 +1368,7 @@ export class DeesTable<T> extends DeesElement {
 
     const effectiveColumns = this.__getEffectiveColumns();
     const visibleCols = effectiveColumns.filter((c) => !c.hidden);
+    const colByKey = new Map<string, Column<T>>(visibleCols.map((c) => [String(c.key), c]));
     const nextSnapshot = new Map<string, Map<string, unknown>>();
     const newlyFlashing = new Map<string, Set<string>>();
 
@@ -1376,7 +1383,26 @@ export class DeesTable<T> extends DeesElement {
       const prevCells = this.__prevSnapshot?.get(rowId);
       if (!prevCells) continue; // new row — not an "update"
       for (const [colKey, nextVal] of cellMap) {
-        if (prevCells.get(colKey) !== nextVal) {
+        const prevVal = prevCells.get(colKey);
+
+        // Look up the column definition for flash options.
+        const colDef = colByKey.get(colKey);
+
+        // Determine whether the cell changed.
+        let changed: boolean;
+        if (colDef?.flashCompare) {
+          // Explicit custom comparator — caller decides.
+          changed = colDef.flashCompare(prevVal, nextVal);
+        } else if (nextVal !== null && nextVal !== undefined && typeof nextVal === 'object') {
+          // Non-primitive (TemplateResult, object, array, etc.) — skip by
+          // default. Custom renderings don't benefit from the text-color
+          // flash and reference inequality causes false positives.
+          changed = false;
+        } else {
+          changed = prevVal !== nextVal;
+        }
+
+        if (changed) {
           // Don't flash the cell the user is actively editing.
           if (
             this.__editingCell &&

ts_web/elements/00group-dataview/dees-table/styles.ts

@@ -404,11 +404,44 @@ export const tableStyles: CSSResult[] = [
         100% { color: var(--dees-color-text-primary); }
       }
 
+      /* Border/background flash variant for cells with styled content
+         (badges, icons, custom components) where a text-color animation
+         would be invisible. Activated via flashBorder on Column. */
+      .innerCellContainer.flashing-border {
+        animation: dees-table-cell-flash-border
+                   var(--dees-table-flash-duration, 900ms)
+                   var(--dees-table-flash-easing);
+        border-radius: 3px;
+      }
+
+      @keyframes dees-table-cell-flash-border {
+        0%,
+        35% {
+          box-shadow: inset 0 0 0 1.5px var(--dees-table-flash-color);
+          background: ${cssManager.bdTheme(
+            'hsl(45 93% 62% / 0.10)',
+            'hsl(45 93% 62% / 0.08)'
+          )};
+        }
+        100% {
+          box-shadow: inset 0 0 0 1.5px transparent;
+          background: transparent;
+        }
+      }
+
       @media (prefers-reduced-motion: reduce) {
         .innerCellContainer.flashing {
           animation: none;
           color: var(--dees-table-flash-color);
         }
+        .innerCellContainer.flashing-border {
+          animation: none;
+          box-shadow: inset 0 0 0 1.5px var(--dees-table-flash-color);
+          background: ${cssManager.bdTheme(
+            'hsl(45 93% 62% / 0.10)',
+            'hsl(45 93% 62% / 0.08)'
+          )};
+        }
       }
 
       /* Dev-time warning banner shown when highlight-updates="flash" but

ts_web/elements/00group-dataview/dees-table/types.ts

@@ -65,6 +65,25 @@ export interface Column<T = any> {
   parse?: (editorValue: any, row: T) => any;
   /** Validate the parsed value before commit. Return string for error, true/void for ok. */
   validate?: (value: any, row: T) => true | string | void;
+
+  // ─── Flash highlight options ───
+
+  /**
+   * Custom comparison for flash-on-update diffing.
+   * Return `true` if the cell should flash (i.e. the values differ).
+   * When absent, non-primitive cell values are skipped entirely
+   * (only strings, numbers, booleans, null, and undefined are diffed).
+   */
+  flashCompare?: (prevVal: any, nextVal: any) => boolean;
+
+  /**
+   * When `true`, flash this cell with a border/background pulse instead of
+   * the default text-color animation. Useful for cells containing styled
+   * badges, icons, or custom web-component renderings where a text-color
+   * change would be invisible.
+   * @default false
+   */
+  flashBorder?: boolean;
 }
 
 /**