feat: add recipe translation tool with AI translation and settings management

- Add Word document parsing and translation export
- Add database configuration management
- Add AI/LLM translation configuration
- Add translation vocabulary management
- Add export settings (colors, page orientation, headers)
- Separate database and AI configurations
- Add debounced search to prevent database overload

app/api/ai/translate/route.ts

@@ -0,0 +1,68 @@
+import { NextRequest, NextResponse } from "next/server";
+import { batchTranslateWithAI, translateWithAI } from "@/lib/ai-translate";
+
+// 单个翻译
+export async function GET(request: NextRequest) {
+  const { searchParams } = new URL(request.url);
+  const word = searchParams.get("word");
+
+  if (!word) {
+    return NextResponse.json({ error: "缺少 word 参数" }, { status: 400 });
+  }
+
+  try {
+    const translation = await translateWithAI(word);
+
+    if (!translation) {
+      return NextResponse.json({ error: "翻译失败" }, { status: 500 });
+    }
+
+    return NextResponse.json({
+      word,
+      english: translation,
+    });
+  } catch (error) {
+    console.error("AI translation error:", error);
+    return NextResponse.json(
+      { error: String(error) },
+      { status: 500 }
+    );
+  }
+}
+
+// 批量翻译
+export async function POST(request: NextRequest) {
+  try {
+    const body = await request.json();
+    const { words } = body as { words: string[] };
+
+    if (!Array.isArray(words) || words.length === 0) {
+      return NextResponse.json({ error: "缺少 words 参数（数组）" }, { status: 400 });
+    }
+
+    // 检查 API Key
+    if (!process.env.AI_API_KEY) {
+      return NextResponse.json({ error: "AI 配置未完成，请先在设置中配置 AI" }, { status: 500 });
+    }
+
+    const results = await batchTranslateWithAI(words);
+
+    // 转换为响应格式
+    const translations: Record<string, string | null> = {};
+    for (const word of words) {
+      translations[word] = results.get(word) || null;
+    }
+
+    return NextResponse.json({
+      translations,
+      total: words.length,
+      success: results.size,
+    });
+  } catch (error) {
+    console.error("AI batch translation error:", error);
+    return NextResponse.json(
+      { error: String(error) },
+      { status: 500 }
+    );
+  }
+}