feat: add word import and class type display controls

app/api/words/import/route.ts

@@ -0,0 +1,34 @@
+import { NextRequest, NextResponse } from "next/server";
+import { importWords, type Grade } from "@/lib/db";
+import { parseWordExcel } from "@/lib/word-excel";
+
+export const runtime = "nodejs";
+export const dynamic = "force-dynamic";
+
+export async function POST(request: NextRequest) {
+  try {
+    const formData = await request.formData();
+    const grade = String(formData.get("grade") ?? "") as Grade;
+    const classTypeId = Number(formData.get("classTypeId"));
+    const file = formData.get("file");
+
+    if (!(file instanceof File)) {
+      return NextResponse.json({ message: "请选择要导入的 Excel 表格" }, { status: 400 });
+    }
+
+    const buffer = Buffer.from(await file.arrayBuffer());
+    const rows = parseWordExcel(buffer);
+    const result = importWords(grade, classTypeId, rows);
+
+    return NextResponse.json({ result });
+  } catch (error) {
+    return NextResponse.json({ message: getErrorMessage(error) }, { status: 400 });
+  }
+}
+
+function getErrorMessage(error: unknown) {
+  const message = error instanceof Error ? error.message : "导入失败";
+  if (message.includes("FOREIGN KEY")) return "班级类型不存在";
+  if (message.includes("Unsupported file")) return "无法读取该表格，请使用 .xlsx 文件";
+  return message;
+}