draft: Add per block MSE for NVFP4 and INT4

[Fridah-nv]

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[codecov]

Codecov Report

❌ Patch coverage is 71.42857% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 74.65%. Comparing base (f06c3f9) to head (c025df7).
⚠️ Report is 5 commits behind head on main.

Files with missing lines	Patch %	Lines
.../torch/quantization/nn/modules/tensor_quantizer.py	60.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #613      +/-   ##
==========================================
+ Coverage   74.57%   74.65%   +0.08%     
==========================================
  Files         183      183              
  Lines       18412    18546     +134     
==========================================
+ Hits        13730    13845     +115     
- Misses       4682     4701      +19     

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[realAsma]

Suggested change

	def blockwise_fp4_fake_quant_kernel(
	def static_blockwise_fp4_fake_quant_kernel(

[realAsma]

line 233:

if is_nvfp4_static: # static per-block
amax = scaled_e4m3_impl(amax, amax.amax()) # fP8 quantization