Gemini 3 Pro returning 400 400 Bad Request

[eignerhandoko]

Describe the bug

Not able to use gemini 3 pro and returns Model call failed: "400 400 Bad Request\n"

Affected version

0.0.375 Commit: fe4913f

Steps to reproduce the behavior

1. Open Copilot
2. Change to model using /model gemini-3-pro-preview
3. Exec prompt

Expected behavior

Should be able to use Gemini 3 Pro model

Additional context

I have enabled Gemini 3 Pro models in Copilot settings

No response