Copilot billing entity isn’t selected

### Describe the bug

I can't save memories anymore since it sas " Copilot billing entity isn’t selected" but ... everything else works on the enterprise setup, and i could save them before,

### Affected version

GitHub Copilot CLI 1.0.65

### Steps to reproduce the behavior

Try to get the agent to save memories, it complains it can't because "Copilot billing entity isn’t selected"

### Expected behavior

Allow it to save memories, or at the very least give a proper explanation of what needs to be enabled or where

### Additional context

_No response_

Start by reproducing the memory-save failure in GitHub Copilot CLI 1.0.65 with an enterprise setup and trace where the “Copilot billing entity isn’t selected” message is produced. Done means memories can be saved, or the error clearly identifies the required setting and where to enable it.

Scritto dal modello di indicizzazione a partire dal testo della issue.