* fix: make Tensor.rand produce correct values for float16
Due to precision loss when casting to float16, the data distribution created by custom_random isnt correctly in the interval ]0, 1[, but instead in the interval ]0, 1], which causes the Tensor.randn to incorrectly generate values of infinity.
The solution uses a scaling value to make sure the values stay under 1, when using half precision.
Closes#3611
* update implementation to truncate to closest f16 value to 1
* chore: fix whitespace
* test larger distribution
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Co-authored-by: chenyu <chenyu@fastmail.com>
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