Add CYD browser flasher with Next.js, i18n, and Web Serial install.

Replace the starter app with a public/local flasher that discovers sibling firmwares, supports en/zh, and documents HTTPS deploy.

Co-authored-by: Cursor <cursoragent@cursor.com>

components/ui/card.tsx

@@ -0,0 +1,44 @@
+import * as React from "react";
+import { cn } from "@/lib/utils";
+
+export function Card({
+  className,
+  ...props
+}: React.HTMLAttributes<HTMLDivElement>) {
+  return (
+    <div
+      className={cn(
+        "rounded-[14px] border border-[var(--line)] bg-[color-mix(in_srgb,var(--bg-elev)_88%,transparent)] p-5 backdrop-blur-sm",
+        className
+      )}
+      {...props}
+    />
+  );
+}
+
+export function CardHeader({
+  className,
+  ...props
+}: React.HTMLAttributes<HTMLDivElement>) {
+  return (
+    <div
+      className={cn("mb-4 flex items-center justify-between gap-4", className)}
+      {...props}
+    />
+  );
+}
+
+export function CardTitle({
+  className,
+  ...props
+}: React.HTMLAttributes<HTMLHeadingElement>) {
+  return (
+    <h2
+      className={cn(
+        "font-[family-name:var(--font-display)] text-[1.05rem] font-bold tracking-tight",
+        className
+      )}
+      {...props}
+    />
+  );
+}