feat(guides): add structured image-first editor

app/api/admin/media/route.ts

@@ -0,0 +1,21 @@
+import { NextResponse } from "next/server";
+
+import { requireAdmin } from "@/lib/auth/server";
+import { uploadPublicMedia } from "@/lib/media/repository";
+
+export async function POST(request: Request) {
+  const admin = await requireAdmin();
+  const form = await request.formData();
+  const file = form.get("file");
+  if (!(file instanceof File)) {
+    return NextResponse.json({ error: "กรุณาเลือกไฟล์รูปภาพ" }, { status: 400 });
+  }
+  try {
+    return NextResponse.json(await uploadPublicMedia(file, admin.user.id), { status: 201 });
+  } catch (cause) {
+    return NextResponse.json(
+      { error: cause instanceof Error ? cause.message : "อัปโหลดไม่สำเร็จ" },
+      { status: 400 },
+    );
+  }
+}