feat(scadabridge): emit scadabridge.deployments.applied on deployment success

src/ZB.MOM.WW.ScadaBridge.DeploymentManager/DeploymentService.cs

@@ -7,6 +7,7 @@ using ZB.MOM.WW.ScadaBridge.Commons.Interfaces.Repositories;
 using ZB.MOM.WW.ScadaBridge.Commons.Interfaces.Services;
 using ZB.MOM.WW.ScadaBridge.Commons.Messages.Deployment;
 using ZB.MOM.WW.ScadaBridge.Commons.Messages.Lifecycle;
+using ZB.MOM.WW.ScadaBridge.Commons.Observability;
 using ZB.MOM.WW.ScadaBridge.Commons.Types;
 using ZB.MOM.WW.ScadaBridge.Commons.Types.Enums;
 using ZB.MOM.WW.ScadaBridge.Commons.Types.Flattening;
@@ -244,6 +245,16 @@ public class DeploymentService
 
             if (response.Status == DeploymentStatus.Success)
             {
+                // Telemetry: one instance deployment successfully applied to a
+                // site. Counted once per successful deploy operation (the unit
+                // of scadabridge.deployments.applied — one DeployInstanceAsync
+                // deploys exactly one instance to one site). Emitted only on this
+                // confirmed-Success path, so failures, timeouts/retries (the
+                // catch block), and the reconciliation path (which recovers a
+                // PRIOR timed-out apply rather than performing a fresh one) do
+                // not increment it.
+                ScadaBridgeTelemetry.RecordDeploymentApplied();
+
                 // The site has applied the deployment. The post-success
                 // persistence below is best-effort: a failure here must be
                 // logged loudly for operator reconciliation but must not flip