Python: [Bug]: Regression on DevUI streaming memory growth issue

[jjwong0915]

Description

In the latest Python release 1.3.0, the same memory growth issue happens again while DevUI streaming answer. It can cause more than 10GB of memory being occupied and cause browser to kill the process containing the web page. See #5221 for more detail.

Code Sample

Error Messages / Stack Traces

Package Versions

agent-framework: 1.3.0

Python Version

Python: 3.14

Additional Context

No response