ci: add Autobahn EVM Interoperability (CON-256)

[wen-coding]

Mirrors the existing "EVM Interoperability" CI job with AUTOBAHN=true
plus the GIGA_EXECUTOR/GIGA_STORAGE/GIGA_OCC flags.

Co-Authored-By: Claude Opus 4.7 (1M context) noreply@anthropic.com

[cursor]

PR Summary

Low Risk
Low risk: CI-only change that adds an additional integration-test matrix entry; main risk is longer runtime or new test flakiness/failures from the extra configuration flags.

Overview
Adds a new "Autobahn EVM Interoperability" entry to the integration-tests matrix in .github/workflows/integration-test.yml, running the existing evm_interoperability_tests.sh under AUTOBAHN=true plus GIGA_EXECUTOR/GIGA_STORAGE/GIGA_OCC env flags to exercise the Autobahn configuration in CI.

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[github-actions]

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Build	Format	Lint	Breaking	Updated (UTC)
✅ passed	✅ passed	✅ passed	✅ passed	May 20, 2026, 3:50 PM