* fix(proxy): bill streamed /v1/completions without stream_options like chat
* test(proxy): mark the text completion stream usage test variable Final
* fix(completions): drop Azure's empty prompt-filter frame when the proxy asked for stream usage
* test(spend): drop the module docstring from the text completion stream usage test
* fix(proxy): keep the internal stream usage strip flag out of the logged request body
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Co-authored-by: mateo-berri <277851410+mateo-berri@users.noreply.github.com>