SubplanService.spawn() now re-records all invariant_enforced decisions from
the parent plan decision tree onto each child plan decision tree. This
satisfies the spec requirement: 'recorded as invariant_enforced decisions that
propagate to child plans.' (Glossary → Invariant)
Previously, child plans started Strategize with a completely empty invariant
set, violating the spec's propagation requirement. non_overridable global
invariants enforced on the parent were not guaranteed to be enforced on child
plans.
The fix adds _propagate_invariant_decisions() to SubplanService which queries
the parent plan's invariant_enforced decisions and re-records each one on the
child plan using DecisionService.record_decision(). The DecisionService is
already injected into SubplanService, so no new dependencies are required.
BDD regression coverage added in features/tdd_invariant_propagation_subplan.feature
with 4 scenarios covering: single invariant propagation, multiple invariant
propagation, non_overridable invariant propagation, and clean spawn with no
parent invariants.
ISSUES CLOSED: #9131
freemo