feat(ui): add Node column + filter to SiteCalls grid

src/ScadaLink.Commons/Messages/Audit/SiteCallQueries.cs

@@ -33,7 +33,8 @@ public sealed record SiteCallQueryRequest(
     DateTime? ToUtc,
     DateTime? AfterCreatedAtUtc,
     Guid? AfterId,
-    int PageSize);
+    int PageSize,
+    string? SourceNodeFilter = null);
 
 /// <summary>
 /// A single <c>SiteCalls</c> row summarised for the Site Calls UI grid. Carries
@@ -61,7 +62,8 @@ public sealed record SiteCallSummary(
     DateTime CreatedAtUtc,
     DateTime UpdatedAtUtc,
     DateTime? TerminalAtUtc,
-    bool IsStuck);
+    bool IsStuck,
+    string? SourceNode = null);
 
 /// <summary>
 /// Central -> Site Calls UI: paginated response for a <see cref="SiteCallQueryRequest"/>.

src/ScadaLink.Commons/Types/Audit/SiteCallQueryFilter.cs

@@ -26,6 +26,11 @@ namespace ScadaLink.Commons.Types.Audit;
 /// keeps the "StuckOnly" filter honest so paging never returns under-filled
 /// pages with a non-null next cursor.
 /// </param>
+/// <param name="SourceNode">
+/// Restrict to cached calls originating at a specific cluster node (e.g.
+/// <c>"site-plant-a-node-a"</c>). Exact match; <c>null</c> means "do not
+/// constrain". Rows with NULL <c>SourceNode</c> are excluded when set.
+/// </param>
 public sealed record SiteCallQueryFilter(
     string? Channel = null,
     string? SourceSite = null,
@@ -33,4 +38,5 @@ public sealed record SiteCallQueryFilter(
     string? Target = null,
     DateTime? FromUtc = null,
     DateTime? ToUtc = null,
-    DateTime? StuckCutoffUtc = null);
+    DateTime? StuckCutoffUtc = null,
+    string? SourceNode = null);