style(chat): 优化聊天界面背景和加载动画样式

- 移除布局中的静态背景资源引用
- 添加动态聊天背景绘制功能
- 调整加载进度条尺寸从50dp改为40dp
- 更新加载动画资源引用路径

app/src/main/java/com/nova/brain/glass/ui/ChatActivity.kt

@@ -3,6 +3,7 @@ package com.nova.brain.glass.ui
 import android.view.View
 import android.widget.TextView
 import com.nova.brain.glass.R
+import com.nova.brain.glass.helper.BgChatDrawable
 import com.nova.brain.glass.databinding.ActivityChatBinding
 import com.nova.brain.glass.helper.OfflineCmdListener
 import com.nova.brain.glass.helper.OfflineCmdServiceHelper
@@ -60,6 +61,10 @@ class ChatActivity : BaseListFormLayoutNormalActivity<ChatItem, ChatVM, Activity
         }
     }
 
+    override fun lateInitView() {
+        recyclerView.background = BgChatDrawable(resources.displayMetrics.density)
+    }
+
     override fun onResume() {
         super.onResume()
         OfflineCmdServiceHelper.addOnLineListener(listener)

app/src/main/res/layout/activity_chat.xml

@@ -11,7 +11,6 @@
             app:layout_constraintStart_toStartOf="parent"
             android:layout_width="match_parent"
             android:layout_height="400dp"
-            android:background="@drawable/bg_chat"
             android:overScrollMode="never" />
         <ProgressBar
             android:id="@+id/pb"
@@ -19,8 +18,8 @@
             app:layout_constraintStart_toStartOf="parent"
             app:layout_constraintEnd_toEndOf="parent"
             app:layout_constraintBottom_toBottomOf="@+id/baseRecyclerView"
-            android:layout_width="50dp"
+            android:layout_width="40dp"
-            android:layout_height="50dp"
+            android:layout_height="40dp"
             android:indeterminateDrawable="@drawable/load_progress" />
 
         <TextView

base/src/main/res/drawable/load_progress.xml

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <rotate xmlns:android="http://schemas.android.com/apk/res/android"
-        android:drawable="@drawable/ic_loading"
+        android:drawable="@drawable/loading"
         android:fromDegrees="0"
         android:pivotX="50%"
         android:pivotY="50%"