Arm backend: Enable capture of debug information during TOSA serialization

[tom-arm]

• Add _serialize_operator() function to NodeVisitor
• Enable passing of DebugHook to NodeVisitor if enabled
• Add option dump_debug_info to ArmCompileSpecBuilder

Change-Id: I9dc8da50a7ef16053b778ab33a03a990035de5ad

cc @digantdesai @freddan80 @per @zingo @oscarandersson8218

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❌ 1 New Failure, 1 Cancelled Job, 1 Pending, 1 Unrelated Failure

As of commit 0137d02 with merge base f8a422c ():

NEW FAILURE - The following job has failed:

• trunk / test-huggingface-transformers-coreml (qwen3-1.7b|xnnpack|--quantize) / macos-job (gh)
  RuntimeError: Command bash /Users/runner/work/_temp/exec_script failed with exit code 138

CANCELLED JOB - The following job was cancelled. Please retry:

• trunk / test-models-macos-cpu (w2l, xnnpack-quantization-delegation) / macos-job (gh)
  ##[error]The operation was canceled.

FLAKY - The following job failed but was likely due to flakiness present on trunk:

• trunk / test-qnn-optimum-model (fp32, roberta) / linux-job (gh) (matched linux rule in flaky-rules.json)
  The process '/usr/bin/git' failed with exit code 128

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[digantdesai]

Can we extend tosa_graph and not overload node visitor with this method?
The tosa_graph_torch (let's say) constructor takes debug_hook or other args and prepares a "graph", through addOperator like methods, which can be observed independently just like an FX graph.

Just an idea, don't want to block this.

[tom-arm]

Thanks for the suggestion Digant. I like the idea, I think it would look a bit cleaner

I can look into this, there will be one/two more commits to finalise this feature. So I think there is scope to incorporate this.