feat(engine): legend rule integration guardrail test

[kiannidev]

Summary

Closes #3425. Adds an integration test ensuring duplicate same-name legendaries trigger ChooseLegend through the GameScenario → SBA path.

Changes

• issue_3425_legend_rule_exemption_scopes.rs control-case test
• Scoped exemption SBA coverage remains in unit tests (feat(engine): SBA coverage for bare tokens legend-rule exemption #3429 / parser in feat(parser): opponent-scoped direct library search prohibition #3428–feat(parser): legend rule exemption for commanders you control #3430)

Implementation method (required)

• Not /engine-implementer — integration test only

CR references

CR 704.5j

Verification

• cargo test -p engine --test integration issue_3425

Made with Cursor

[gemini-code-assist]

Warning

You have reached your daily quota limit. Please wait up to 24 hours and I will start processing your requests again!

[matthewevans]

Control-case integration guardrail (CR 704.5j): two duplicate legendaries with no exemption must trigger ChooseLegend through the real GameScenario -> check_state_based_actions path. Discriminating, complements the exemption-suppression unit tests landed in #3429. Verified passing on local merge of origin/main on warm target. Closes #3425.