fix(site-runtime): deployment whose Instance Actor dies during init reports Failed, exactly-once reply (S6)

Success now requires BOTH persistence commit AND an InstanceActorInitialized
readiness signal from the actor's PreStart — persistence can commit before the
actor's async init has run or failed, so persistence alone must not report
Success. An actor that dies during init never signals readiness; the Terminated
fallback fails that deployment and rolls back the optimistic state. The
persisted-row rollback is deferred until the store commits so it cannot race the
optimistic write.

Deviation from plan Task 15: the plan's swallow-only guard did not handle the
persistence-first ordering (empirically the store commits before the Terminated
signal, so Success was reported for a dead actor). Added the readiness handshake
to make the join deterministic.

tests/ZB.MOM.WW.ScadaBridge.SiteRuntime.Tests/Actors/DeploymentManagerRedeployTests.cs

@@ -360,4 +360,38 @@ public class DeploymentManagerRedeployTests : TestKit, IDisposable
                 r.Message.Contains("terminated unexpectedly", StringComparison.OrdinalIgnoreCase));
         }, TimeSpan.FromSeconds(10));
     }
+
+    [Fact]
+    public async Task Deploy_WhoseActorDiesDuringInit_ReportsFailed_NotSuccess()
+    {
+        // A deploy whose config compiles (passing the compile gate) but whose Instance
+        // Actor dies during init must report Failed — NOT the Success it used to report
+        // once SQLite persisted, leaving the deployer believing a dead instance is live
+        // (S6). The reply must be exactly-once.
+        var actor = CreateDeploymentManager();
+        await Task.Delay(500); // empty startup
+
+        actor.Tell(new DeployInstanceCommand(
+            "dep-dies", "dies-on-init", "r1",
+            CtorThrowingConfig("dies-on-init"), "admin", DateTimeOffset.UtcNow));
+
+        var resp = ExpectMsg<DeploymentStatusResponse>(TimeSpan.FromSeconds(10));
+        Assert.Equal(DeploymentStatus.Failed, resp.Status);
+
+        // Exactly one reply — no late Success from the persistence path.
+        ExpectNoMsg(TimeSpan.FromMilliseconds(500));
+
+        // The optimistically-persisted config row is rolled back so a restart does not
+        // re-create the failing actor. The rollback is fire-and-forget once the store
+        // commits, so poll for it rather than reading once.
+        List<DeployedInstance> configs = [];
+        for (var i = 0; i < 50; i++)
+        {
+            configs = await _storage.GetAllDeployedConfigsAsync();
+            if (configs.All(c => c.InstanceUniqueName != "dies-on-init"))
+                break;
+            await Task.Delay(100);
+        }
+        Assert.DoesNotContain(configs, c => c.InstanceUniqueName == "dies-on-init");
+    }
 }