fix: 备注去掉"备注:"前缀，只显示纯内容

前缀和内容拼接后视觉不统一，绿色背景已能区分备注区域

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app/src/main/java/com/xiaoqu/watch/ui/task/TaskListFragment.kt

@@ -377,7 +377,7 @@ class TaskListFragment : BaseFragment<FragmentTaskListBinding>() {
             else -> null
         }
         if (note != null) {
-            binding.tvNote.text = "备注: $note"
+            binding.tvNote.text = note
             binding.tvNote.visibility = View.VISIBLE
         }
     }