fix: preserve layout validation errors

apps/nextjs/src/app/[locale]/boards/[name]/settings/_layout.tsx

@@ -111,9 +111,6 @@ export const LayoutSettingsContent = ({ board, form, isSaving, saveSettingsAsync
 
   const nextBreakpoint = getNextCustomBreakpoint(form.values.layouts);
   const baseLayout = form.values.layouts.find((layout) => layout.role === "base");
-  const sortedLayouts = form.values.layouts
-    .map((layout, index) => ({ layout, index }))
-    .toSorted((entryA, entryB) => entryA.layout.breakpoint - entryB.layout.breakpoint);
 
   return (
     <SectionCard title={tBoard("setting.section.layout.title")}>
@@ -129,25 +126,25 @@ export const LayoutSettingsContent = ({ board, form, isSaving, saveSettingsAsync
             disabled={nextBreakpoint === null || !baseLayout}
             onClick={() => {
               if (nextBreakpoint === null || !baseLayout) return;
-              form.setFieldValue("layouts", [
+              const newLayout: FormValues["layouts"][number] = {
-                ...form.values.layouts,
+                id: createId(),
-                {
+                name: tBoard("setting.section.layout.custom.defaultName"),
-                  id: createId(),
+                columnCount: baseLayout.columnCount,
-                  name: tBoard("setting.section.layout.custom.defaultName"),
+                leftGutterColumnCount: baseLayout.leftGutterColumnCount,
-                  columnCount: baseLayout.columnCount,
+                rightGutterColumnCount: baseLayout.rightGutterColumnCount,
-                  leftGutterColumnCount: baseLayout.leftGutterColumnCount,
+                breakpoint: nextBreakpoint,
-                  rightGutterColumnCount: baseLayout.rightGutterColumnCount,
+                role: "custom",
-                  breakpoint: nextBreakpoint,
+              };
-                  role: "custom",
+              let insertionIndex = form.values.layouts.findIndex((layout) => layout.breakpoint > nextBreakpoint);
-                },
+              if (insertionIndex === -1) insertionIndex = form.values.layouts.length;
-              ]);
+              form.insertListItem("layouts", newLayout, insertionIndex);
             }}
           >
             {tBoard("setting.section.layout.responsive.action.add")}
           </Button>
         </Group>
 
-        {sortedLayouts.map(({ layout, index }) => {
+        {form.values.layouts.map((layout, index) => {
           const persistedLayout = board.layouts.find((candidate) => candidate.id === layout.id);
           const sourceLayout = persistedLayout ?? board.layouts.find((candidate) => candidate.role === "base");
           const customBreakpoints = form.values.layouts