加入可朗讀的圖卡

在自主學中文新專案中，複刻自主學英文的Flashcards功能。

有圖的卡片，可以朗讀中文(台灣口音)就好。
不需要翻面功能，不需要朗讀英文。

圖片用webp格式，可以加速載入

已放在專案目錄的public/img資料夾

Look for existing flashcard components in the codebase, likely in the 'learn-en' project for reference. The images are in public/img/. Need to implement a card component that displays a webp image and integrates text-to-speech for Mandarin (Taiwan accent). Check how audio playback is handled elsewhere in the project. The feature is done when a user can see an image card and hear the Chinese pronunciation.

Scritto dal modello di indicizzazione a partire dal testo della issue.