[API] Create stable APIs for PyTorch 2.5

[justinchuby]

Create stable APIs for PyTorch 2.5 so that it does not need to use any internal ONNX Script APIs. Created APIs are

"check_model",
"convert_version",
"get_torchlib_ops",
"optimize",
"save_model_with_external_data",

In pytorch, it is expected to write:

import onnxscript._framework_apis.torch_2_5

Fixes #1827

[codecov]

Codecov Report

Attention: Patch coverage is 38.33333% with 37 lines in your changes missing coverage. Please review.

Project coverage is 75.04%. Comparing base (e037aa0) to head (014c676).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
onnxscript/_framework_apis/torch_2_5.py	38.33%	37 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1832      +/-   ##
==========================================
- Coverage   75.13%   75.04%   -0.09%     
==========================================
  Files         248      249       +1     
  Lines       26977    27037      +60     
  Branches     4926     4937      +11     
==========================================
+ Hits        20268    20291      +23     
- Misses       5762     5800      +38     
+ Partials      947      946       -1     

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[github-actions]

Test Results

     24 files  ±0      24 suites  ±0   2h 41m 36s ⏱️ - 10m 28s
 14 119 tests ±0  11 748 ✅ +1    2 333 💤 ±0   32 ❌  - 1   6 🔥 ±0 
354 880 runs  ±0  81 040 ✅ +1  273 586 💤 ±0  212 ❌  - 1  42 🔥 ±0 

For more details on these failures and errors, see this check.

Results for commit 014c676. ± Comparison against base commit e037aa0.

♻️ This comment has been updated with latest results.