Summary

Deliver first end-to-end tuple-domain path where feasible tuples from data define sparse variable instantiation semantics.

Parent: #183
Execution Mode: HITL

Acceptance criteria

• Tuple-domain variables instantiate only on declared feasible tuples.
• x[a,i,g,b] is treated as tuple-membership semantics, not Cartesian semantics.
• Tuple component schema must be explicit in declarations (not inferred).
• Tuple component order is enforced as canonical for the declared tuple set.
• Basic happy-path compile test demonstrates sparse instantiation.

Blocked by

• None