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# Summary

This PR adds a ScalingGranularity Enum, and threads it though the stack to all the places we call 'tensor_to_amax" and tensor_to_scale.
 - Currently hardcodes TensroWise.Scaling in Float8Linear, Float8DynamicLinear, Float8InferenceLinear. Asserts that granularity is TensorWise for now.
 -  Added this as a property of WeightWithDynamicFloat8CastTensor, since we need to know a prior how do do the scaling for fp8 comms.  



### Testing

``` Shell
============================================================================= test session starts =============================================================================
platform linux -- Python 3.12.4, pytest-7.4.0, pluggy-1.5.0
rootdir: /home/drisspg/meta/float8_experimental
plugins: hypothesis-6.104.1
collected 9 items                                                                                                                                                             

test/test_fsdp2/test_fsdp2_eager.py .........                                                                                                                           [100%]

============================================================================= 9 passed in 30.77s ==============================================================================
all tests successful

```





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