copilot cli error while using opus 4.5 and sonnet 4.5

### Describe the bug

❌ Error: (query) Execution failed: Error: Failed to get response from the AI model; retried 5 times (total retry wait time: 93.00126834108823 seconds) Last error: CAPIError: 503 {"error":{"message":"HTTP/2 GOAWAY connection terminated","type":"connection_error"}}

### Affected version

_No response_

### Steps to reproduce the behavior

_No response_

### Expected behavior

_No response_

### Additional context

_No response_

No file, test, version, or reproduction steps are identified in the report. Start by reproducing the Copilot CLI query with Opus 4.5 and Sonnet 4.5, then trace the retry path around the HTTP/2 GOAWAY and 503 errors; done should mean the reported failure is addressed and covered by a regression check.

Written by the indexing model from the issue text.