Request: Ollama API Key return to Bring Your Own Model

### Describe the feature or problem you'd like to solve

Add Ollama apiKeyEnv API Key to Github Copilot Bring Your Own Model Menu

### Proposed solution

I have a local Ollama server that I want to use remotely and need the API Key to set the host header.

Otherwise, I will need to use a forward proxy server to add the header back and it seems like a wasted effort.

I am using my other API key endpoints

### Example prompts or workflows

This allows me to use my 38GB to 80GB models without token costs or high electricity costs

### Additional context

Start at the Bring Your Own Model menu and trace how API key environment variables are represented for other endpoints. Check how the Ollama host header is configured, then verify that selecting Ollama accepts and forwards the requested API key without requiring a proxy.

Written by the indexing model from the issue text.