fix(bb): guard component analyzer range-list mapping

[AztecBot]

Summary

The nightly barretenberg debug build is failing in acir_components_check_tests AcirComponentsCheckTest.DetectsUnconstrainedWitnesses with _GLIBCXX_DEBUG aborting on std::vector<unsigned int>::operator[]: witness/range-list index 10 is read from a real_variable_index vector resized to 9 entries.

Root cause: the component checker deliberately simulates a missing witness mapping by shrinking builder.real_variable_index, but the circuit static analyzer and the checker range-list collection still assumed every variable index in range-list metadata could be mapped through real_variable_index. Release builds did not catch this, while the debug STL correctly aborted before the checker could return its intended UNCONSTRAINED error.

This PR:

• routes static-analyzer constant/range-list mapping through to_real()
• makes to_real() tolerate stale builder variable references by mapping them to zero_idx()
• skips invalid range-list entries in ComponentsChecker so missing witnesses remain reported as unconstrained instead of crashing

CI evidence: http://ci.aztec-labs.com/32410024cc115505 from run https://github.com/AztecProtocol/barretenberg-claude/actions/runs/30333232782.

Tests

• NATIVE_PRESET=debug AVM=0 AVM_TRANSPILER=0 cmake --build --preset debug --target acir_components_check_tests
• NATIVE_PRESET=debug AVM=0 AVM_TRANSPILER=0 scripts/run_test.sh acir_components_check_tests AcirComponentsCheckTest.DetectsUnconstrainedWitnesses
• ./build-debug/bin/acir_components_check_tests
• cmake --build --preset debug --target boomerang_value_detection_tests
• ./build-debug/bin/boomerang_value_detection_tests
• git diff --check

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Created by claudebox · group: slackbot