[Progress] ProgressNotification The message field is missing.

[Zhaobudaoyuema]

hello. I noticed that the 3.26 version specification added a message field for progress updates. However, I couldn’t find it in the current 1.6.0 Python SDK. Could you please let me know when it will be supported?

[aksheyd]

This would be my first PR but could I try adding this @dsp-ant?

I'm thinking of adding the type to the class, adding it as an arg to send_progress_notification() in client/server/shared, editing shared/progress.py, and adding a test case.