Add multi-board selector and scalable firmware catalog UI.

Board chips reserve future models; firmware uses searchable cards with detail pane and optional meta.json media/docs.

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

app/api/firmware/[project]/[variant]/media/[...path]/route.ts

@@ -0,0 +1,43 @@
+import fs from "fs";
+import path from "path";
+import { NextResponse } from "next/server";
+import { resolveMediaFile } from "@/lib/firmware";
+
+export const dynamic = "force-dynamic";
+
+const MIME: Record<string, string> = {
+  ".png": "image/png",
+  ".jpg": "image/jpeg",
+  ".jpeg": "image/jpeg",
+  ".webp": "image/webp",
+  ".gif": "image/gif",
+  ".mp4": "video/mp4",
+  ".webm": "video/webm",
+  ".md": "text/markdown; charset=utf-8",
+  ".txt": "text/plain; charset=utf-8",
+  ".html": "text/html; charset=utf-8",
+  ".pdf": "application/pdf",
+};
+
+type Params = {
+  params: Promise<{ project: string; variant: string; path: string[] }>;
+};
+
+export async function GET(_req: Request, { params }: Params) {
+  const { project, variant, path: parts } = await params;
+  const rel = parts.join("/");
+  const abs = resolveMediaFile(project, variant, rel);
+  if (!abs) {
+    return NextResponse.json({ error: "not found" }, { status: 404 });
+  }
+
+  const ext = path.extname(abs).toLowerCase();
+  const buf = fs.readFileSync(abs);
+  return new NextResponse(buf, {
+    headers: {
+      "Content-Type": MIME[ext] || "application/octet-stream",
+      "Content-Length": String(buf.length),
+      "Cache-Control": "public, max-age=3600",
+    },
+  });
+}