feat: add word import and class type display controls

app/api/words/export/route.ts

@@ -0,0 +1,25 @@
+import { NextRequest } from "next/server";
+import { listWords } from "@/lib/db";
+import { buildWordExcel } from "@/lib/word-excel";
+
+export const runtime = "nodejs";
+export const dynamic = "force-dynamic";
+
+export async function GET(request: NextRequest) {
+  const searchParams = request.nextUrl.searchParams;
+  const grade = searchParams.get("grade") ?? undefined;
+  const classTypeId = Number(searchParams.get("classTypeId"));
+  const words = listWords({
+    grade,
+    classTypeId: Number.isFinite(classTypeId) && classTypeId > 0 ? classTypeId : undefined,
+  });
+  const workbook = buildWordExcel(words);
+
+  return new Response(workbook, {
+    headers: {
+      "Content-Type": "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
+      "Content-Disposition": `attachment; filename="${encodeURIComponent("词库导入表格")}.xlsx"`,
+      "Cache-Control": "no-store",
+    },
+  });
+}