feat(metrics): add compilation phases

[giladchase]

Summary

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• Bug fix (fixes incorrect behavior)
• New feature
• Performance improvement
• Documentation change with concrete technical impact
• Style, wording, formatting, or typo-only change

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What was the behavior or documentation before?

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What is the behavior or documentation after?

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Related issue or discussion (if any)

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[reviewable-StarkWare]

This change is 

[giladchase]

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This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
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• feat(metrics): add compilation phases #9403 👈 (View in Graphite)
• feat(metrics): add incremental mode logic #9402
• feat: add cairo-metrics benchmark harness + CI tracking #9401
• main

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[github-actions]

Benchmark Comparison

Benchmark                                 Baseline       Current      Diff

corelib-clean-casm-walltime               522.8 ms      524.9 ms     +0.4% [SLOWER]
corelib-clean-diagnostics-walltime         22.80 s       22.61 s     -0.8% [faster]
corelib-clean-full-walltime                26.90 s       26.44 s     -1.7% [faster]
corelib-clean-sierra-walltime              26.45 s       26.35 s     -0.4% [faster]
perpetual-clean-casm-walltime                 0 ns          0 ns     +0.0% 
perpetual-clean-diagnostics-walltime          0 ns          0 ns     +0.0% 
perpetual-clean-full-walltime                 0 ns          0 ns     +0.0% 
perpetual-clean-sierra-walltime               0 ns          0 ns     +0.0%