merge: external-system retry policy end-to-end (register row 27) — MaxRetries/RetryDelay now travel artifact→gRPC→site schema→S&F enqueue, CLI --max-retries/--retry-delay-seconds, ArtifactDiff compares them

src/ZB.MOM.WW.ScadaBridge.Commons/Messages/Artifacts/ExternalSystemArtifact.cs

@@ -1,9 +1,41 @@
 namespace ZB.MOM.WW.ScadaBridge.Commons.Messages.Artifacts;
 
+/// <summary>
+/// A single external HTTP system, flattened for deployment to a site.
+/// </summary>
+/// <param name="Name">Unique system name — the key scripts call it by.</param>
+/// <param name="EndpointUrl">Base URL of the system's HTTP endpoint.</param>
+/// <param name="AuthType">Authentication type identifier (e.g. <c>ApiKey</c>, <c>BasicAuth</c>).</param>
+/// <param name="AuthConfiguration">JSON-serialized authentication configuration for <paramref name="AuthType"/>.</param>
+/// <param name="MethodDefinitionsJson">JSON-serialized method list, or <c>null</c> when the system defines none.</param>
+/// <param name="TimeoutSeconds">
+/// Per-system HTTP round-trip timeout in seconds. <c>0</c> = unset — the gateway's configured
+/// <c>DefaultHttpTimeout</c> applies.
+/// </param>
+/// <param name="MaxRetries">
+/// Store-and-Forward retry budget for this system's cached calls. <c>0</c> = unset — the engine's
+/// <c>DefaultMaxRetries</c> applies.
+/// <para>
+/// <b>0 means "unset", not "no limit", at THIS layer</b> — the inverse of
+/// <c>StoreAndForwardMessage.MaxRetries</c>, where a stored 0 means unbounded retry. The two
+/// meanings are reconciled in <c>ExternalSystemClient.CachedCallAsync</c>, which passes a 0
+/// through as <c>null</c> so the bounded engine default applies rather than an unbounded retry
+/// loop. Keeping "unset" as 0 here (rather than a nullable) matches
+/// <see cref="DatabaseConnectionArtifact"/>, the non-nullable
+/// <c>ExternalSystemDefinition.MaxRetries</c> entity property this is projected from, and the
+/// proto3 scalar it is carried on.
+/// </para>
+/// </param>
+/// <param name="RetryDelay">
+/// Fixed interval between Store-and-Forward retry sweeps for this system's cached calls.
+/// <see cref="TimeSpan.Zero"/> = unset — the engine's <c>DefaultRetryInterval</c> applies.
+/// </param>
 public record ExternalSystemArtifact(
     string Name,
     string EndpointUrl,
     string AuthType,
     string? AuthConfiguration,
     string? MethodDefinitionsJson,
-    int TimeoutSeconds = 0);
+    int TimeoutSeconds = 0,
+    int MaxRetries = 0,
+    TimeSpan RetryDelay = default);

src/ZB.MOM.WW.ScadaBridge.Commons/Messages/Management/ExternalSystemCommands.cs

@@ -2,8 +2,23 @@ namespace ZB.MOM.WW.ScadaBridge.Commons.Messages.Management;
 
 public record ListExternalSystemsCommand;
 public record GetExternalSystemCommand(int ExternalSystemId);
-public record CreateExternalSystemCommand(string Name, string EndpointUrl, string AuthType, string? AuthConfiguration, int? TimeoutSeconds = null);
-public record UpdateExternalSystemCommand(int ExternalSystemId, string Name, string EndpointUrl, string AuthType, string? AuthConfiguration, int? TimeoutSeconds = null);
+/// <summary>
+/// Creates an external HTTP system.
+/// </summary>
+/// <remarks>
+/// <paramref name="MaxRetries"/> and <paramref name="RetryDelay"/> are the Store-and-Forward
+/// retry policy applied to this system's <c>ExternalSystem.CachedCall</c> buffering. Both are
+/// nullable on the wire so "omit" is distinguishable from "set to 0"; a null (or an explicit 0)
+/// stores the entity's unset value, which the site gateway translates into the engine's
+/// <c>DefaultMaxRetries</c>/<c>DefaultRetryInterval</c>.
+/// </remarks>
+public record CreateExternalSystemCommand(string Name, string EndpointUrl, string AuthType, string? AuthConfiguration, int? TimeoutSeconds = null, int? MaxRetries = null, TimeSpan? RetryDelay = null);
+
+/// <summary>
+/// Updates an external HTTP system. Nullable members follow the "omit to preserve" convention —
+/// a null leaves the stored value untouched.
+/// </summary>
+public record UpdateExternalSystemCommand(int ExternalSystemId, string Name, string EndpointUrl, string AuthType, string? AuthConfiguration, int? TimeoutSeconds = null, int? MaxRetries = null, TimeSpan? RetryDelay = null);
 public record DeleteExternalSystemCommand(int ExternalSystemId);
 
 // External System Methods