fix(ui): stabilize tool header icons and mcp completion label

static/src/styles/components/chat/_chat-area.scss

@@ -594,10 +594,12 @@
 
 .arrow {
     width: 16px;
+    min-width: 16px;
     height: 16px;
     display: flex;
     align-items: center;
     justify-content: center;
+    flex: 0 0 16px;
     transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
     color: var(--claude-text-secondary);
 }
@@ -618,7 +620,7 @@
     display: inline-flex;
     align-items: center;
     justify-content: center;
-    flex-shrink: 0;
+    flex: 0 0 20px;
 }
 
 .captured-status {

static/src/utils/chatDisplay.ts

@@ -145,6 +145,30 @@ function describeReadFileResult(tool: any): string {
   return '文件读取完成';
 }
 
+function isMcpTool(tool: any): boolean {
+  const name = String(tool?.name || '');
+  return name.startsWith('mcp__');
+}
+
+function getMcpToolDisplayName(tool: any): string {
+  const customDisplayName = String(tool?.display_name || '').trim();
+  if (customDisplayName) {
+    return customDisplayName;
+  }
+  const name = String(tool?.name || '').trim();
+  if (!name.startsWith('mcp__')) {
+    return name || 'MCP 工具';
+  }
+  const parts = name.split('__').filter(Boolean);
+  if (parts.length >= 3) {
+    const remoteName = parts.slice(2).join('__').trim();
+    if (remoteName) {
+      return remoteName;
+    }
+  }
+  return name || 'MCP 工具';
+}
+
 export function getToolStatusText(tool: any, opts?: { intentEnabled?: boolean }): string {
   if (!tool) {
     return '';
@@ -161,6 +185,11 @@ export function getToolStatusText(tool: any, opts?: { intentEnabled?: boolean })
     return tool.message;
   }
 
+  // MCP 工具完成态统一显示：<工具名> 执行完成（避免刷新前后文案不一致）
+  if (tool.status === 'completed' && isMcpTool(tool)) {
+    return `${getMcpToolDisplayName(tool)} 执行完成`;
+  }
+
   // 开启时：有 intent 就只显示 intent
   if (intentEnabled && hasIntent) {
     return intentText;