Resolve all 46 low-severity architecture review findings

src/ZB.MOM.WW.ScadaBridge.CentralUI/Components/Health/CentralFailoverControl.razor

@@ -1,10 +1,9 @@
 @using ZB.MOM.WW.ScadaBridge.CentralUI.Auth
-@inject Microsoft.AspNetCore.Components.Authorization.AuthenticationStateProvider MutationAuth
 @using Microsoft.AspNetCore.Components.Authorization
 @using ZB.MOM.WW.ScadaBridge.CentralUI.Components.Shared
 @using ZB.MOM.WW.ScadaBridge.CentralUI.Services
 @using ZB.MOM.WW.ScadaBridge.Security
-@inject IManualFailoverService Failover
+@inject AuthorizedManualFailoverService Failover
 @inject IDialogService Dialog
 
 @* Admin-only manual failover of the central pair (decision 2026-07-22). Rendered on the
@@ -94,11 +93,10 @@
 
         try
         {
-            var actor = await MutationAuth.RequireRoleAsync(ZB.MOM.WW.ScadaBridge.Security.Roles.Administrator);
 
             if (IsSite)
             {
-                var outcome = await Failover.FailOverSiteAsync(SiteId!, actor);
+                var outcome = await Failover.FailOverSiteAsync(SiteId!);
                 if (outcome.Accepted)
                 {
                     _message = $"Failover triggered — {outcome.TargetAddress} is leaving the site cluster.";
@@ -113,7 +111,7 @@
             }
             else
             {
-                var target = await Failover.FailOverCentralAsync(actor);
+                var target = await Failover.FailOverCentralAsync();
                 if (target is null)
                 {
                     // The server-side peer guard refused. Never report a failover that did not happen.