Thinking Tokens/Text never appears with BYOK models regardless of endpoint type

### Describe the bug

Thinking Tokens/Text never appears with BYOK models regardless of endpoint type

### Affected version

1.0.61

### Steps to reproduce the behavior

Ask a question or any directive that would cause the model to think. And you will observe that the Thinking text or thinking tokens never appear on the display regardless of the settings you give to co-pilot.

### Expected behavior

As user I'm expecting to see the thinking text that the model is going through while it's contemplating or thinking what to do.

### Additional context

In many occasions I just don't know if the connection is lost or is there a bug, because I do not observe the model thinking. Also when it's thinking for too long I have no way or recourse of observing if it went into a thinking loop.

No source files, tests, or entry points are named in the issue. Reproduce the problem with a BYOK model across the endpoint types and relevant Copilot settings, then trace where model thinking output should reach the display. Done means thinking text or token updates are visible while the model is processing.

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