fix: user/assistant alignment via outer row justify-content (reliable in Vela)

src/pages/index/index.ux

@@ -20,7 +20,8 @@
 
         <!-- 消息流 -->
         <scroll class="chat-scroll" scroll-y="true">
-          <div class="chat-msg {{$item.role === 'user' ? 'msg-user' : 'msg-assistant'}}" for="{{messages}}">
+          <div class="msg-row {{$item.role === 'user' ? 'row-user' : 'row-assistant'}}" for="{{messages}}">
+            <div class="chat-msg {{$item.role === 'user' ? 'msg-user' : 'msg-assistant'}}">
               <div class="think-chip" if="{{$item.think}}">
                 <text>💭 思考…</text>
               </div>
@@ -34,6 +35,7 @@
                 <input class="approve-btn deny" type="button" value="拒绝" />
               </div>
             </div>
+          </div>
         </scroll>
 
         <!-- 底部输入栏 -->
@@ -667,25 +669,35 @@ export default {
   margin-top: 4px;
 }
 
+.msg-row {
+  width: 100%;
+  flex-direction: row;
+  margin-bottom: 6px;
+}
+
+.row-user {
+  justify-content: flex-end;
+}
+
+.row-assistant {
+  justify-content: flex-start;
+}
+
 .chat-msg {
   width: auto;
   max-width: 84%;
   flex-direction: column;
-  margin-bottom: 6px;
   padding: 7px 10px;
   border-radius: 12px;
 }
 
 .msg-user {
-  align-self: flex-end;
-  margin-left: auto;
   margin-right: 12px;
   background-color: rgba(51, 180, 255, 0.20);
   border: 1px solid rgba(120, 200, 255, 0.30);
 }
 
 .msg-assistant {
-  align-self: flex-start;
   margin-left: 12px;
   margin-right: 12px;
   background-color: rgba(58, 62, 70, 0.55);