[WebGPU] Support PIX Capture for WebGPU EP (#23192)
PIX Capture tool requires 'present' to end a frame capture. ORT doesn't
have rendering work so no 'present' happens.
To avoid endless waiting for PIX capture tool, this PR added a blank
surface and 'present' on it in each session run.
The surface is created in WebGPU ep constructor and closed in WebGPU ep
destructor.
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