docs: complete XML doc coverage (returns, summaries, inheritdoc)

Resolve all 622 issues flagged by the enhanced CommentChecker: add missing
<returns> tags (incl. the standard phrasing on non-generic Task methods),
add missing <summary> tags, and replace misused/redundant <inheritdoc/> on
members that override or implement nothing with real documentation.
Documentation-only — no behavior change; solution builds clean.

src/ZB.MOM.WW.ScadaBridge.CentralUI/Services/ApiMethodKeyScopeReconciler.cs

@@ -45,6 +45,7 @@ public static class ApiMethodKeyScopeReconciler
     /// <param name="currentMethodsByKey">Each affected key's CURRENT full scope set, keyed by KeyId.
     /// Read fresh from the seam right before reconciling so concurrent edits do not get clobbered.</param>
     /// <param name="keyNamesById">Display names by KeyId, for human-readable empty-scope messages.</param>
+    /// <returns>A <see cref="ReconcileResult"/> with the scope updates to apply and any empty-scope warnings.</returns>
     public static ReconcileResult Reconcile(
         string methodName,
         IReadOnlySet<string> selectedKeyIds,

src/ZB.MOM.WW.ScadaBridge.CentralUI/Services/AuditEventView.cs

@@ -70,6 +70,8 @@ public sealed record AuditEventView
     /// <summary>
     /// Decomposes a canonical <see cref="AuditEvent"/> into a flat view for the UI.
     /// </summary>
+    /// <param name="evt">The canonical audit event to decompose.</param>
+    /// <returns>A flat <see cref="AuditEventView"/> populated from the event's top-level and details fields.</returns>
     public static AuditEventView From(AuditEvent evt)
     {
         var r = AuditRowProjection.Decompose(evt);

src/ZB.MOM.WW.ScadaBridge.CentralUI/Services/AuditLogExportService.cs

@@ -42,6 +42,7 @@ public interface IAuditLogExportService
     /// enough to amortise the per-query overhead, small enough that one page in
     /// memory is bounded.
     /// </param>
+    /// <returns>A task that completes when all matching rows (up to <paramref name="maxRows"/>) have been written to <paramref name="output"/>.</returns>
     Task ExportAsync(
         AuditLogQueryFilter filter,
         int maxRows,
@@ -176,6 +177,7 @@ public sealed class AuditLogExportService : IAuditLogExportService
     /// cleanly on another.
     /// </summary>
     /// <param name="evt">The audit event view to format as a CSV row.</param>
+    /// <returns>An RFC 4180 CSV row string (no trailing newline) for the supplied event.</returns>
     internal static string FormatCsvRow(AuditEventView evt)
     {
         var sb = new StringBuilder(256);

src/ZB.MOM.WW.ScadaBridge.CentralUI/Services/IAuditLogQueryService.cs

@@ -28,6 +28,7 @@ public interface IAuditLogQueryService
     /// <param name="filter">Filter criteria applied to the audit log query.</param>
     /// <param name="paging">Optional paging cursor; defaults to first page when null.</param>
     /// <param name="ct">Cancellation token.</param>
+    /// <returns>A task that resolves to a page of audit event views matching the filter.</returns>
     Task<IReadOnlyList<AuditEventView>> QueryAsync(
         AuditLogQueryFilter filter,
         AuditLogPaging? paging = null,
@@ -57,6 +58,7 @@ public interface IAuditLogQueryService
     /// dashboard.
     /// </remarks>
     /// <param name="ct">Cancellation token.</param>
+    /// <returns>A task that resolves to the current audit KPI snapshot.</returns>
     Task<AuditLogKpiSnapshot> GetKpiSnapshotAsync(CancellationToken ct = default);
 
     /// <summary>
@@ -76,6 +78,7 @@ public interface IAuditLogQueryService
     /// </remarks>
     /// <param name="executionId">Any execution id in the chain to look up.</param>
     /// <param name="ct">Cancellation token.</param>
+    /// <returns>A task that resolves to the flat list of execution tree nodes in the chain.</returns>
     Task<IReadOnlyList<ExecutionTreeNode>> GetExecutionTreeAsync(
         Guid executionId,
         CancellationToken ct = default);
@@ -90,5 +93,6 @@ public interface IAuditLogQueryService
     /// filter affordance.
     /// </summary>
     /// <param name="ct">Cancellation token.</param>
+    /// <returns>A task that resolves to the distinct non-null source node names present in the audit log.</returns>
     Task<IReadOnlyList<string>> GetDistinctSourceNodesAsync(CancellationToken ct = default);
 }

src/ZB.MOM.WW.ScadaBridge.CentralUI/Services/IBindingTester.cs

@@ -31,6 +31,7 @@ public interface IBindingTester
     /// <param name="connectionName">Name of the site-local data connection — the site's <c>DataConnectionManagerActor</c> indexes its children by name.</param>
     /// <param name="tagPaths">Tag paths to read.</param>
     /// <param name="ct">Cancellation token.</param>
+    /// <returns>A task that resolves to the read outcomes for all requested tag paths.</returns>
     Task<ReadTagValuesResult> ReadAsync(
         string siteId,
         string connectionName,

src/ZB.MOM.WW.ScadaBridge.CentralUI/Services/IBrowseService.cs

@@ -29,6 +29,7 @@ public interface IBrowseService
     /// <param name="connectionName">Name of the site-local data connection to browse against — the site's <c>DataConnectionManagerActor</c> indexes its children by name.</param>
     /// <param name="parentNodeId">Node to browse, or <c>null</c> to browse from the server root.</param>
     /// <param name="cancellationToken">Cancellation token.</param>
+    /// <returns>A task that resolves to a <see cref="BrowseNodeResult"/> containing child nodes or a <see cref="BrowseFailure"/> on error.</returns>
     Task<BrowseNodeResult> BrowseChildrenAsync(
         string siteId,
         string connectionName,