[Misc] Capture and log the time of loading weights

[waltforme]

This PR tries to introduce more transparency to weights loading.

Today we're already logging the memory footprint Loading model weights took X GB.
We can do even better by also logging the time consumption like Loading model weights took X seconds.

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[njhill]

@waltforme could we add it in the same log statement as the size, to avoid an extra line in the logs?

[waltforme]

@waltforme could we add it in the same log statement as the size, to avoid an extra line in the logs?

@njhill Great idea!
I merged it with the log statement for the size.
Also added same logging for V0.

[njhill]

Thanks @waltforme