[code-reflection] RFR: Integrated PartialEvaluator into Onnx

[Adam Sotona]

Integrated PartialEvaluator into Onnx for loops unrolling + related LLM support.

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Commit messages:
 - TensorDataStream helper class
 - fixed OnnxTransformer
 - unrolled LLMs - work in progress
 - unrolled LLMs - work in progress
 - PartialEvaluator integration into Onnx
 - support for constant arrays in returned tuples/records
 - constant arrays return - part 1
 - support for constant array initializers
 - indexed named parameters in tuples
 - expanding constant arrays in method paramters into tuples
 - ... and 2 more: https://git.openjdk.org/babylon/compare/47c1459b...ae5270e3

Changes: https://git.openjdk.org/babylon/pull/462/files
  Webrev: https://webrevs.openjdk.org/?repo=babylon&pr=462&range=00
  Stats: 338 lines in 11 files changed: 308 ins; 0 del; 30 mod
  Patch: https://git.openjdk.org/babylon/pull/462.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/462/head:pull/462

PR: https://git.openjdk.org/babylon/pull/462