feat(adminui): thread User.Identity.Name into Deployments createdBy (F18)

Injects AuthenticationStateProvider and reads the current user's identity
name on Deploy click, replacing the "(current user)" placeholder.
Anonymous case falls back to "(anonymous)" — should never hit in practice
since the page requires FleetAdmin/ConfigEditor.

src/Server/ZB.MOM.WW.OtOpcUa.AdminUI/Components/Pages/Deployments.razor

@@ -1,5 +1,6 @@
 @page "/deployments"
 @using Microsoft.AspNetCore.Authorization
+@using Microsoft.AspNetCore.Components.Authorization
 @using Microsoft.EntityFrameworkCore
 @using ZB.MOM.WW.OtOpcUa.Commons.Interfaces
 @using ZB.MOM.WW.OtOpcUa.Commons.Messages.Admin
@@ -12,6 +13,7 @@
 
 @inject IDbContextFactory<OtOpcUaConfigDbContext> DbFactory
 @inject IAdminOperationsClient AdminOps
+@inject AuthenticationStateProvider AuthState
 @rendermode InteractiveServer
 
 <PageTitle>Deployments</PageTitle>
@@ -103,8 +105,10 @@
         _lastMessage = null;
         try
         {
+            var auth = await AuthState.GetAuthenticationStateAsync();
+            var createdBy = auth.User.Identity?.Name ?? "(anonymous)";
             var result = await AdminOps.StartDeploymentAsync(
-                createdBy: "(current user)", // F18: thread HttpContext.User.Identity.Name through
+                createdBy: createdBy,
                 ct: CancellationToken.None);
 
             _lastSuccess = result.Outcome == StartDeploymentOutcome.Accepted;