Capture rewrite rule name as metadata

[gramalingam]

Capture rewrite rule name as metadata to simplify debugging issues from rewrites. This is just a basic version.

TODO / Extensions:

• Sometimes we apply a sequence of rewrite-rules one after another, to perform complex fusions. This currently records only the last rule applied.
• This can be solved when we merge metadata from original nodes into new nodes. (See [DRAFT] Merge metadata props when fusing #2375 )
• May be useful standardize on a single ONNX metadata key for "source" info (that can be used by torchlib/other exporters/rewriter/optimizer etc.)

[codecov]

Codecov Report

❌ Patch coverage is 97.05882% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 70.47%. Comparing base (5be9d3b) to head (484f1a6).
⚠️ Report is 1 commits behind head on main.
✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
onnxscript/rewriter/pattern_test.py	96.66%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2675      +/-   ##
==========================================
+ Coverage   70.43%   70.47%   +0.03%     
==========================================
  Files         224      224              
  Lines       26778    26812      +34     
  Branches     2680     2686       +6     
==========================================
+ Hits        18862    18895      +33     
- Misses       6985     6986       +1     
  Partials      931      931              

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[justinchuby]

Sometimes we apply a sequence of rewrite-rules one after another, to perform complex fusions. This currently records only the last rule applied.

Releated: #2671