新增搜索标题和网页标题双字段

- 数据库新增 search_title 字段存储搜索结果标题
- product_names 存储抓取到的网页标题
- 搜索页面显示两个标题（搜索标题 + 网页标题）
- 内容库页面也显示两个标题

models/database.py

@@ -32,6 +32,7 @@ class Database:
                 CREATE TABLE IF NOT EXISTS articles (
                     id INTEGER PRIMARY KEY AUTOINCREMENT,
                     product_names TEXT NOT NULL,
+                    search_title TEXT,
                     category TEXT,
                     keywords TEXT,
                     summary TEXT,
@@ -44,6 +45,12 @@ class Database:
                 )
             ''')
             
+            # 为旧表添加字段（如果不存在）
+            try:
+                cursor.execute('ALTER TABLE articles ADD COLUMN search_title TEXT')
+            except:
+                pass
+            
             # 待处理产品列表
             cursor.execute('''
                 CREATE TABLE IF NOT EXISTS pending_products (
@@ -138,15 +145,15 @@ class Database:
             conn.commit()
 
 # ========== 内容库操作 ==========
-    def add_article(self, product_names, category, keywords, summary, content, source, url=None):
+    def add_article(self, product_names, category, keywords, summary, content, source, url=None, search_title=None):
         """添加文章到内容库"""
         with self.get_connection() as conn:
             cursor = conn.cursor()
             cursor.execute('''
-                INSERT INTO articles (product_names, category, keywords, summary, content, source, url)
-                VALUES (?, ?, ?, ?, ?, ?, ?)
-            ''', (json.dumps(product_names, ensure_ascii=False), category, 
-                  json.dumps(keywords, ensure_ascii=False), summary, content, source, url))
+                INSERT INTO articles (product_names, search_title, category, keywords, summary, content, source, url)
+                VALUES (?, ?, ?, ?, ?, ?, ?, ?)
+            ''', (json.dumps(product_names, ensure_ascii=False), search_title,
+                  category, json.dumps(keywords, ensure_ascii=False), summary, content, source, url))
             conn.commit()
             return cursor.lastrowid