改成可搜尋，並且換成2.5pro模型

gemini.py

@@ -8,8 +8,11 @@ from io import BytesIO
 import markdown
 from bs4 import BeautifulSoup
 from flask import Flask, abort, request, send_from_directory
+
 from google import genai
 from google.genai import types
+from google.genai.types import Tool, GenerateContentConfig, GoogleSearch
+
 from linebot.v3 import WebhookHandler
 from linebot.v3.exceptions import InvalidSignatureError
 from linebot.v3.messaging import (
@@ -32,9 +35,11 @@ from PIL import Image
 # === 初始化 Google Gemini ===
 GOOGLE_API_KEY = os.environ.get("GOOGLE_API_KEY")
 client = genai.Client(api_key=GOOGLE_API_KEY)
-chat = client.chats.create(model="gemini-2.0-flash",
-    config=types.GenerateContentConfig(
-        system_instruction="你是一個中文的AI助手，請用繁體中文回答"    
+chat = client.chats.create(model="gemini-2.5-pro-preview-05-06",
+    config=GenerateContentConfig(
+        system_instruction="你是一個中文的AI助手，請用繁體中文回答",
+        tools=[google_search_tool],
+        response_modalities=["TEXT"], 
     )
 )