feat(commons): project outbound API/DB/notification rows onto the External lane

ResolveKind maps ApiOutbound/DbOutbound/Notification to ApiCall/DbCall/Notify;
ResolveLane puts the three on FlowLane.External; outbound outcomes map
Delivered→Ok, Failed→Failed, Parked/Discarded→Parked, else Pending; subtitles
'{status} · sync|cached', '{op} · n rows' from a DbWrite Extra, '{status}' for
Notify. New FlowStepProjector.IsOutbound helper.

Claude-Session: https://claude.ai/code/session_01NcMG6xXdsJbmD2wYAgkK29

src/ZB.MOM.WW.ScadaBridge.Commons/Types/Debugging/FlowStepProjector.cs

@@ -1,3 +1,4 @@
+using System.Text.Json;
 using ZB.MOM.WW.Audit;
 using ZB.MOM.WW.ScadaBridge.Commons.Types.Audit;
 using ZB.MOM.WW.ScadaBridge.Commons.Types.Enums;
@@ -73,17 +74,34 @@ public static class FlowStepProjector
         return FlowStepKind.Unknown;
     }
 
-    /// <summary>Lane rule: route call / inbound / response → Central; script run / wait → Site; write → Tags.</summary>
+    /// <summary>Lane rule: route call / inbound / response → Central; script run / wait → Site; write → Tags; outbound API / DB / notify → External.</summary>
     public static FlowLane ResolveLane(FlowStepKind kind, string? sourceSiteId) => kind switch
     {
         FlowStepKind.InboundRequest or FlowStepKind.RouteCall or FlowStepKind.Response => FlowLane.Central,
         FlowStepKind.ScriptRun or FlowStepKind.AttributeWait => FlowLane.Site,
         FlowStepKind.AttributeWrite => FlowLane.Tags,
+        FlowStepKind.ApiCall or FlowStepKind.DbCall or FlowStepKind.Notify => FlowLane.External,
         _ => string.IsNullOrEmpty(sourceSiteId) ? FlowLane.Central : FlowLane.Site,
     };
 
+    /// <summary>True for the three outbound kinds that live on the External lane.</summary>
+    public static bool IsOutbound(FlowStepKind kind)
+        => kind is FlowStepKind.ApiCall or FlowStepKind.DbCall or FlowStepKind.Notify;
+
     private static FlowStepOutcome ResolveOutcome(FlowStepKind kind, string? status, string? error)
     {
+        if (IsOutbound(kind))
+        {
+            return status switch
+            {
+                nameof(AuditStatus.Delivered) => FlowStepOutcome.Ok,
+                nameof(AuditStatus.Failed) => FlowStepOutcome.Failed,
+                nameof(AuditStatus.Parked) or nameof(AuditStatus.Discarded) => FlowStepOutcome.Parked,
+                // Submitted / Forwarded / Attempted — and anything this build does not know — is still in flight.
+                _ => FlowStepOutcome.Pending,
+            };
+        }
+
         if (!string.Equals(status, nameof(AuditStatus.Failed), StringComparison.Ordinal))
             return FlowStepOutcome.Ok;
         if ((kind == FlowStepKind.ScriptRun || kind == FlowStepKind.AttributeWait)
@@ -107,6 +125,45 @@ public static class FlowStepProjector
             : extra.WaitOutcome is null
                 ? extra.ObservedValue
                 : extra.ObservedValue is null ? extra.WaitOutcome : $"{extra.WaitOutcome} · {extra.ObservedValue}",
+        FlowStepKind.ApiCall => string.Equals(d.Kind, nameof(AuditKind.ApiCall), StringComparison.Ordinal)
+            ? $"{d.Status} · sync"
+            : $"{d.Status} · cached",
+        FlowStepKind.DbCall => DbSubtitle(d),
+        FlowStepKind.Notify => d.Status,
         _ => d.Kind,
     };
+
+    /// <summary>
+    /// A sync <c>DbWrite</c> row carries <c>{"op":"write","rowsAffected":n}</c> / <c>{"op":"read","rowsReturned":n}</c>
+    /// in <c>Extra</c> (site <c>AuditingDbCommand</c> vocabulary); cached rows carry none and read as <c>"{status} · cached"</c>.
+    /// </summary>
+    private static string? DbSubtitle(AuditDetails d)
+    {
+        if (string.Equals(d.Kind, nameof(AuditKind.DbWrite), StringComparison.Ordinal) && !string.IsNullOrWhiteSpace(d.Extra))
+        {
+            try
+            {
+                using var doc = JsonDocument.Parse(d.Extra);
+                var root = doc.RootElement;
+                if (root.ValueKind == JsonValueKind.Object && root.TryGetProperty("op", out var opEl) && opEl.ValueKind == JsonValueKind.String)
+                {
+                    var op = opEl.GetString();
+                    int? rows = null;
+                    if (root.TryGetProperty("rowsAffected", out var ra) && ra.ValueKind == JsonValueKind.Number) rows = ra.GetInt32();
+                    else if (root.TryGetProperty("rowsReturned", out var rr) && rr.ValueKind == JsonValueKind.Number) rows = rr.GetInt32();
+                    if (rows is { } n && n >= 0)
+                        return $"{op} · {n} {(n == 1 ? "row" : "rows")}";
+                    return op;
+                }
+            }
+            catch (JsonException)
+            {
+                // Fall through — an unparseable Extra never fails projection.
+            }
+        }
+
+        return string.Equals(d.Kind, nameof(AuditKind.DbWrite), StringComparison.Ordinal)
+            ? d.Status
+            : $"{d.Status} · cached";
+    }
 }