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

lib/ai-translate.ts

@@ -0,0 +1,139 @@
+import OpenAI from "openai";
+
+// AI 翻译配置
+interface AIConfig {
+  apiKey: string;
+  baseUrl?: string;
+  model?: string;
+}
+
+// 默认配置（从环境变量）
+function getDefaultConfig(): AIConfig {
+  return {
+    apiKey: process.env.AI_API_KEY || "",
+    baseUrl: process.env.AI_BASE_URL || undefined,
+    model: process.env.AI_MODEL || "gpt-3.5-turbo",
+  };
+}
+
+// 模块级配置存储
+let savedConfig: AIConfig | null = null;
+
+// 设置保存的配置
+export function setAIConfig(config: AIConfig) {
+  savedConfig = config;
+}
+
+// 获取配置（优先使用保存的配置）
+export function getAIConfig(): AIConfig {
+  return savedConfig || getDefaultConfig();
+}
+
+// 解析翻译结果
+function parseTranslation(content: string): string | null {
+  const patterns = [
+    /english\s*:\s*['"]([^'"]+)['"]/i,
+    /english\s*[:\s]+([^,'"\n]+)/i,
+    /['"]([^'"]+)['"]\s*[,}].*english/i,
+    /^([^,]+)\s*,\s*english\s*:\s*['"]([^'"]+)['"]/i,
+  ];
+
+  for (const pattern of patterns) {
+    const match = content.match(pattern);
+    if (match) {
+      return match[1]?.trim() || null;
+    }
+  }
+
+  return null;
+}
+
+// 翻译单个词组（带重试）
+export async function translateWithAI(
+  word: string,
+  config?: AIConfig,
+  maxRetries: number = 3
+): Promise<string | null> {
+  const aiConfig = config || getAIConfig();
+
+  if (!aiConfig.apiKey) {
+    throw new Error("AI API Key 未配置");
+  }
+
+  const client = new OpenAI({
+    apiKey: aiConfig.apiKey,
+    baseURL: aiConfig.baseUrl,
+  });
+
+  const prompt = `你是一个专业的中文到英文翻译助手。
+
+任务：将给定的中文词组翻译成英文。
+
+严格要求：
+1. 必须严格返回 JSON 格式：{"word":"中文原文","english":"英文翻译"}
+2. 不要返回任何其他内容，不要解释
+3. 只返回这一行 JSON
+4. 翻译要简洁、准确
+
+中文词组：${word}
+
+请立即返回 JSON 结果：`;
+
+  for (let attempt = 0; attempt < maxRetries; attempt++) {
+    try {
+      const completion = await client.chat.completions.create({
+        model: aiConfig.model || "gpt-3.5-turbo",
+        messages: [
+          {
+            role: "system",
+            content: "你是一个严格遵循指令的翻译助手。必须只返回要求的 JSON 格式，不要返回任何其他内容。",
+          },
+          { role: "user", content: prompt },
+        ],
+        temperature: 0,
+        max_tokens: 50,
+      });
+
+      const content = completion.choices[0]?.message?.content || "";
+      const translation = parseTranslation(content);
+
+      if (translation && translation.length > 0) {
+        return translation;
+      }
+
+      // Fallback: 提取英文单词
+      const fallbackMatch = content.match(/[a-zA-Z][a-zA-Z\s-]*/);
+      if (fallbackMatch) {
+        const fallback = fallbackMatch[0].trim();
+        if (fallback.length > 1) {
+          return fallback;
+        }
+      }
+    } catch (error) {
+      console.error(`Attempt ${attempt + 1} error:`, error);
+    }
+  }
+
+  return null;
+}
+
+// 批量翻译词组
+export async function batchTranslateWithAI(
+  words: string[],
+  config?: AIConfig
+): Promise<Map<string, string>> {
+  const results = new Map<string, string>();
+
+  for (const word of words) {
+    try {
+      const translation = await translateWithAI(word, config);
+      if (translation) {
+        results.set(word, translation);
+      }
+    } catch (error) {
+      console.error(`Failed to translate "${word}":`, error);
+    }
+  }
+
+  return results;
+}