feat: rebuild board grid experience

apps/nextjs/src/components/layout/header/button.tsx

@@ -1,4 +1,4 @@
-import type { ForwardedRef, ReactNode } from "react";
+import type { FocusEventHandler, ForwardedRef, PointerEventHandler, ReactNode } from "react";
 import { forwardRef } from "react";
 import type { ActionIconProps } from "@mantine/core";
 import { ActionIcon } from "@mantine/core";
@@ -8,6 +8,8 @@ import { Link } from "@homarr/ui";
 type HeaderButtonProps = (
   | {
       onClick?: () => void;
+      onFocus?: FocusEventHandler<HTMLButtonElement>;
+      onPointerEnter?: PointerEventHandler<HTMLButtonElement>;
     }
   | {
       href: string;

apps/nextjs/src/components/layout/viewport-hint.tsx

@@ -0,0 +1,28 @@
+"use client";
+
+import { useEffect } from "react";
+
+import { boardViewportWidthCookieName } from "@homarr/boards/layout-selection";
+
+export const ViewportHint = () => {
+  useEffect(() => {
+    let timeout: ReturnType<typeof setTimeout> | undefined;
+    const persist = () => {
+      const viewportWidth = document.documentElement.clientWidth || window.innerWidth;
+      document.cookie = `${boardViewportWidthCookieName}=${Math.round(viewportWidth)}; Path=/; Max-Age=31536000; SameSite=Lax`;
+    };
+    const handleResize = () => {
+      clearTimeout(timeout);
+      timeout = setTimeout(persist, 150);
+    };
+
+    persist();
+    window.addEventListener("resize", handleResize, { passive: true });
+    return () => {
+      clearTimeout(timeout);
+      window.removeEventListener("resize", handleResize);
+    };
+  }, []);
+
+  return null;
+};