feat(scripts): realign Test Run with runtime API, add anonymous-object calls and instance binding

The Test Run sandbox and Monaco analysis modelled a script API that had
drifted from the site runtime's ScriptGlobals, so real scripts failed to
compile in Test Run. Realign both to the runtime surface
(Instance/Scripts/ExternalSystem/Attributes/Children/Parent) and drop the
duplicate ScriptHost stub so the two cannot diverge again.

- Script calls (Scripts.CallShared, Instance.CallScript, Route.To().Call)
  accept an anonymous object instead of a hand-built dictionary, via a
  shared ScriptArgs normalizer; existing dictionary calls still compile.
- Test Run can optionally bind to a deployed instance, so Instance/
  Attributes/CallScript route to it cross-site; adds site-side
  RouteToGetAttributes/RouteToSetAttributes handlers.
- Adds Test Run panels to the API method and template script editors.
- Fixes the TestDatabaseQuery seed script, which queried a table that
  never existed.

Also commits unrelated in-progress work already in the tree: the health
monitoring report loop, site streaming changes, and the Admin/Design
data-connection and SMTP page reorganization.

src/ScadaLink.CentralUI/Components/Pages/Monitoring/Health.razor

@@ -51,10 +51,11 @@
             </div>
         </div>
 
-        @* Per-site detail cards *@
-        @foreach (var (siteId, state) in _siteStates.OrderBy(s => s.Key))
+        @* Per-site detail cards — central cluster pinned to the top, then sites alphabetically *@
+        @foreach (var (siteId, state) in _siteStates.OrderBy(s => s.Key == CentralHealthReportLoop.CentralSiteId ? 0 : 1).ThenBy(s => s.Key))
         {
-            var siteName = GetSiteName(siteId);
+            var isCentral = siteId == CentralHealthReportLoop.CentralSiteId;
+            var siteName = isCentral ? "Central Cluster" : GetSiteName(siteId);
             var detailsCollapseId = $"site-details-{siteId}";
             <div class="card mb-3">
                 <div class="card-header d-flex justify-content-between align-items-center py-2">
@@ -67,10 +68,12 @@
                         {
                             <span class="badge bg-danger me-2" aria-label="State: Offline">@OfflineGlyph Offline</span>
                         }
-                        <strong class="fs-5">@siteName (@siteId)</strong>
+                        <strong class="fs-5">@siteName@(isCentral ? "" : $" ({siteId})")</strong>
                     </div>
                     <small class="text-muted">
-                        Last report: <TimestampDisplay Value="@state.LastReportReceivedAt" Format="HH:mm:ss" /> | Seq: @state.LastSequenceNumber
+                        Last report: <TimestampDisplay Value="@state.LastReportReceivedAt" Format="HH:mm:ss" />
+                        | Last heartbeat: <TimestampDisplay Value="@state.LastHeartbeatAt" Format="HH:mm:ss" />
+                        | Seq: @state.LastSequenceNumber
                     </small>
                 </div>
                 <div class="card-body p-3">