Gate inbox delivery on worker-side steer ACK

Replace the fire-and-forget steer with a correlated ACK round-trip so main
only marks an inbox row delivered once the worker confirms the message
landed on the live Agent. Steer against a run that is still in the
`preparing` window or has already started `closing` now falls back to the
wake + inbox projection path instead of being silently dropped.

Worker publishes `run-agent-state` transitions at Agent construction and
teardown; main tracks these on `ActiveRunContext.state` and refuses to
steer runs that are not `agent_active`. A rejected or timed-out ACK
triggers `wakeAgentIfPossible` so the next `prepareRun` replays the row.

src/main/service-graph.ts

@@ -171,6 +171,7 @@ export function createServiceGraph(deps: ServiceGraphDependencies) {
       budgetService: leaf.budgetEnforcementService,
       sessionService: leaf.sessionManagementService,
       piRuntimeRef,
+      getRuntimeMessageInjector: () => runtimeMessageInjector,
     });
 
     runtimeMessageInjector = new RuntimeMessageInjector({
@@ -181,6 +182,11 @@ export function createServiceGraph(deps: ServiceGraphDependencies) {
         if (!worker) throw new Error("Worker is not initialised — cannot deliver steer message.");
         worker.postMessage(message);
       },
+      getWakeAgent: () => {
+        if (!orchestrationRef.isAssigned()) return null;
+        const orch = orchestrationRef.get();
+        return (agentId, companyId, trigger) => orch.wakeAgentIfPossible(agentId, companyId, trigger);
+      },
       logger,
     });