Realize aggregate interaction budgets in the reference runtime #1532

Problem

#1469 (ACT-624) attaches interaction budgets to the behavior-specification aggregate, so human, scripted, replayed, policy-directed and mixed-control participants can carry one, but the reference runtime does not realize them. Its nonclaims say:

The reference runtime does not reserve, commit, reset or reconcile an aggregate budget. Its v3 autonomous enforcement is unchanged.

To keep the gap from being bypassed, #1469 makes the control plane refuse a manual action of a governed participant unless the backend declares interaction_budgets, and planner admission refuses an aggregate budget unless the backend declares the feature. The reference backends do not declare it (the stub manifest fixture lists interaction_budgets with limitation:interaction_budgets:not-realized), so a scenario that gives a human or scripted participant an aggregate budget cannot run on the reference runtime at all, and the budget rules are exercised only through conformance on evidence that another backend records.

Scope

• Reserve, commit, release, reset and reconcile aggregate budgets in the reference runtime with the same accounting the v3 autonomous path uses (feat!: define participant budget exhaustion and limit-effect semantics #1466), for every participant kind the aggregate can govern, including manual actions submitted through the control plane.
• Declare interaction_budgets for the reference runtime once it enforces them, and record the evidence that the feat: make interaction budgets a first-class participant behavior member #1469 conformance check reads.

Done when

• A scenario with an aggregate budget on a human or scripted participant plans and runs on the reference runtime.
• The reference runtime refuses the attempt that exceeds the aggregate budget, records the reserve, commit or reject events, and resets at the declared boundary.
• The feat: make interaction budgets a first-class participant behavior member #1469 conformance check passes on the evidence the reference runtime records, and fails when an event is removed.
• The nonclaim is removed from the ACT-624 section.

Related

• feat: make interaction budgets a first-class participant behavior member #1469 (noted it), Participant Interaction Budgets And Quotas (ACT-624) #310 (ACT-624), feat!: define participant budget exhaustion and limit-effect semantics #1466, feat: support authored participant interaction budgets #1467