feat: 新增文字错题录入功能，修复乱码

templates/subject_detail.html

@@ -56,7 +56,7 @@
       <i class="fa-solid fa-image mr-1.5"></i>上传错题图片
     </button>
     <button id="tabText" onclick="switchTab('text')" class="tab-btn flex-1 py-2.5 rounded-xl text-sm font-medium transition bg-gray-100 text-gray-500 hover:bg-gray-50">
-      <i class="fa-solid fa-keyboard mr-1.5"></i>文字录���错题
+      <i class="fa-solid fa-keyboard mr-1.5"></i>文字录入错题
     </button>
   </div>