Avoid materializing unused tuple fields

[Frotty]

Summary

• resolve tuple selection against scalarized storage before expanding array or member reads
• follow nested tuple component paths so only the selected scalar leaf (or selected subtree) is materialized
• preserve one-time evaluation and source order for effectful receivers and indexes
• add optimized-Lua coverage for plain, effectful, nested, and class-field tuple reads

Verification

• ./gradlew test --tests "tests.wurstscript.tests.LuaBackendAuditTests.tuplesAreScalarizedWithoutLuaAllocations" --tests "tests.wurstscript.tests.LuaBackendAuditTests.tupleMemberArrayAssignmentCapturesIndex" --tests "tests.wurstscript.tests.LuaBackendAuditTests.tupleSelectionPreservesLeftToRightEvaluation" --tests "tests.wurstscript.tests.LuaBackendAuditTests.unreadTupleReturnSlotsAreRemoved" --tests "tests.wurstscript.tests.LuaBackendAuditTests.discardedTupleComponentsThatCanFailAreStillEvaluated" --tests "tests.wurstscript.tests.LuaBackendAuditTests.tupleFieldReadsOnlyLoadTheSelectedStorageComponent"
• ./gradlew test --tests "tests.wurstscript.tests.TupleTests"
• the new regression failed on the parent commit with points_x/y and Entity_pos_x/y discard calls, then passed with only the selected backing reads

Scope

• tuple-return selection remains covered by the existing unread-return-slot regression
• no inliner, register-budget, spill fallback, assurance, or integer arithmetic lowering changes
• production-map counts and performance remain to be measured against a fresh parent-commit baseline

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-04T23:26:13.016851Z	5ad7edb	PR opened

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