feat: complete T-105b account login reuse

app/cdp.py

@@ -43,6 +43,20 @@ def close_tab(target_id, host=None):
     return response.ok
 
 
+def activate_tab(target_id, host=None):
+    """Bring an existing Chrome target/page to the foreground."""
+
+    if not target_id:
+        return False
+    ver = http_get("/json/version", host=host)
+    b = CDP(ver["webSocketDebuggerUrl"])
+    try:
+        b.send("Target.activateTarget", {"targetId": target_id})
+    finally:
+        b.close()
+    return True
+
+
 class CDP:
     """单个 target 的 CDP 客户端：命令同步、事件回调异步。"""