Dashboard: replace inline fully-qualified type refs with @using

ApiKeysPage and GalaxyPage referenced ApiKeyConstraints and
GalaxyRepositoryOptions by full namespace inside @code. Add the
appropriate @using directive at the top of each file and let the
short type names resolve through that.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/ZB.MOM.WW.MxGateway.Server/Dashboard/Components/Pages/ApiKeysPage.razor

@@ -1,5 +1,6 @@
 @page "/apikeys"
 @inherits DashboardPageBase
+@using ZB.MOM.WW.MxGateway.Server.Security.Authentication
 @inject AuthenticationStateProvider AuthenticationStateProvider
 @inject IDashboardApiKeyManagementService ApiKeyManagementService
 
@@ -416,7 +417,7 @@ else
             KeyId: CreateModel.KeyId,
             DisplayName: CreateModel.DisplayName,
             Scopes: CreateModel.SelectedScopes,
-            Constraints: new ZB.MOM.WW.MxGateway.Server.Security.Authentication.ApiKeyConstraints(
+            Constraints: new ApiKeyConstraints(
                 ReadSubtrees: ParseList(CreateModel.ReadSubtrees),
                 WriteSubtrees: ParseList(CreateModel.WriteSubtrees),
                 ReadTagGlobs: ParseList(CreateModel.ReadTagGlobs),
@@ -447,7 +448,7 @@ else
         }
     }
 
-    private static string ConstraintText(ZB.MOM.WW.MxGateway.Server.Security.Authentication.ApiKeyConstraints constraints)
+    private static string ConstraintText(ApiKeyConstraints constraints)
     {
         if (constraints.IsEmpty)
         {

src/ZB.MOM.WW.MxGateway.Server/Dashboard/Components/Pages/GalaxyPage.razor

@@ -1,5 +1,6 @@
 @page "/galaxy"
 @inherits DashboardPageBase
+@using ZB.MOM.WW.MxGateway.Server.Galaxy
 
 <PageTitle>Dashboard Galaxy</PageTitle>
 
@@ -140,7 +141,7 @@ else
 
 @code {
     [Inject]
-    private IOptions<ZB.MOM.WW.MxGateway.Server.Galaxy.GalaxyRepositoryOptions> GalaxyOptions { get; set; } = null!;
+    private IOptions<GalaxyRepositoryOptions> GalaxyOptions { get; set; } = null!;
 
     private string RefreshHeading()
     {