fix: ignore sortersChanged for non-existent columns (#9734)

Following up on the AI reproduction, `Grid.sortersChanged` no longer
throws when a sorter references a column that was removed on the server
between the client emitting the event and the server handling it. The
stale sorter is now skipped and any remaining valid sorters are still
applied.

Fixes #1201

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Co-authored-by: claude[bot] <41898282+claude[bot]@users.noreply.github.com>
Co-authored-by: Sergey Vinogradov <5039436+vursen@users.noreply.github.com>

Author: vursen

vaadin-grid-flow-parent/vaadin-grid-flow/src/main/java/com/vaadin/flow/component/grid/Grid.java

@@ -4028,8 +4028,10 @@ private void sortersChanged(ArrayNode sorters) {
             JsonNode sorter = sorters.get(i);
             Column<T> column = idToColumnMap.get(sorter.get("path").asString());
             if (column == null) {
-                throw new IllegalArgumentException(
-                        "Received a sorters changed call from the client for a non-existent column");
+                // The column may have been removed on the server between the
+                // client emitting the event and the server handling it. Skip
+                // the stale sorter.
+                continue;
             }
             if (sorter.has("direction") && sorter.get("direction")
                     .getNodeType() == JsonNodeType.STRING) {

vaadin-grid-flow-parent/vaadin-grid-flow/src/test/java/com/vaadin/flow/component/grid/GridSortingTest.java

@@ -247,6 +247,32 @@ void changing_sorters() {
                 testSortListener.events.get(1).getSortOrder());
     }
 
+    @Test
+    void sortersChanged_forRemovedColumn_sorterIgnored() {
+        // A sortersChanged call can reference a column that was removed on the
+        // server between the client emitting the event and the server handling
+        // it. Such stale sorters should be ignored, not throw.
+        ArrayNode sortersArray = JacksonUtils.createArrayNode();
+        sortersArray.add(createSortObject(getColumnId(nameColumn), "asc"));
+        sortersArray.add(createSortObject("non-existent-column", "desc"));
+        callSortersChanged(sortersArray);
+
+        assertSortOrdersEquals(GridSortOrder.asc(nameColumn).build(),
+                testSortListener.events.get(0).getSortOrder());
+    }
+
+    @Test
+    void sortersChanged_onlyRemovedColumn_sortCleared() {
+        setTestSorting();
+
+        ArrayNode sortersArray = JacksonUtils.createArrayNode();
+        sortersArray.add(createSortObject("non-existent-column", "asc"));
+        callSortersChanged(sortersArray);
+
+        assertSortOrdersEquals(List.of(),
+                testSortListener.events.get(1).getSortOrder());
+    }
+
     @Test
     void template_renderer_non_comparable_property() {
         Column<Person> column = grid.addColumn(LitRenderer.<Person> of("")