* fix: Use eval_duration for output TPS calculations and add as a metric field
* refactor usage of eval_duration from ollama metrics
* move eval_duration to usage
* overwrite duration in ollama provider wip measureAsyncFunction optional param
* allow for overloaded duration in measureAsyncFunction
* simplify flow for duration tracking
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Co-authored-by: shatfield4 <seanhatfield5@gmail.com>
Co-authored-by: Timothy Carambat <rambat1010@gmail.com>