feat(audit): MxGateway canonical SQLite audit_event store + IAuditWriter + IApiKeyAuditStore->canonical adapter (Task 2.3)

src/ZB.MOM.WW.MxGateway.Server/Security/Authentication/AuthStoreServiceCollectionExtensions.cs

@@ -1,10 +1,12 @@
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.Options;
+using ZB.MOM.WW.Audit;
 using ZB.MOM.WW.Auth.Abstractions.ApiKeys;
 using ZB.MOM.WW.Auth.ApiKeys;
 using ZB.MOM.WW.Auth.ApiKeys.Admin;
 using ZB.MOM.WW.Auth.ApiKeys.DependencyInjection;
 using ZB.MOM.WW.Auth.ApiKeys.Sqlite;
+using ZB.MOM.WW.MxGateway.Server.Security.Audit;
 
 namespace ZB.MOM.WW.MxGateway.Server.Security.Authentication;
 
@@ -64,6 +66,33 @@ public static class AuthStoreServiceCollectionExtensions
         // migrator and the migration hosted service.
         services.AddZbApiKeyAuth(effectiveConfig, AuthenticationSectionPath);
 
+        // Canonical audit (Task 2.3 — DEEP adopt ZB.MOM.WW.Audit). All MxGateway audit flows as a
+        // canonical AuditEvent through the library IAuditWriter, persisted in a NEW gateway-owned
+        // audit_event table that lives in the SAME SQLite DB file as the api-key stores (it reuses
+        // the library's AuthSqliteConnectionFactory, registered by AddZbApiKeyAuth above).
+        services.AddSingleton(sp =>
+            new SqliteCanonicalAuditStore(sp.GetRequiredService<AuthSqliteConnectionFactory>()));
+        // Resolve the logger defensively: the production host always registers ILogger<T>, but the
+        // DI-only auth/CLI/dashboard unit tests build a bare ServiceCollection without AddLogging().
+        // Fall back to NullLogger there so the audit writer (and the IApiKeyAuditStore override that
+        // depends on it) still resolve. The write path is best-effort regardless.
+        services.AddSingleton<IAuditWriter>(sp =>
+            new CanonicalAuditWriter(
+                sp.GetRequiredService<SqliteCanonicalAuditStore>(),
+                sp.GetService<ILogger<CanonicalAuditWriter>>()
+                    ?? Microsoft.Extensions.Logging.Abstractions.NullLogger<CanonicalAuditWriter>.Instance));
+
+        // OVERRIDE the library's IApiKeyAuditStore (AddZbApiKeyAuth registered the library's
+        // SqliteApiKeyAuditStore via TryAddSingleton) with an adapter that canonicalizes every
+        // library-emitted ApiKeyAuditEntry onto AuditEvent and forwards it through IAuditWriter.
+        // This is the only way to canonicalize the library-internal ApiKeyAdminCommands verbs
+        // (create/revoke/rotate/init-db, etc.), which we cannot edit. The adapter is registered
+        // after AddZbApiKeyAuth so it (last registration) is what ApiKeyAdminCommands resolves and
+        // what the dashboard "recent audit" view reads via IApiKeyAuditStore.ListRecentAsync.
+        // The library's api_key_audit table is left in place but is now UNUSED — nothing writes to
+        // it once this adapter replaces the library's audit store.
+        services.AddSingleton<IApiKeyAuditStore, CanonicalForwardingApiKeyAuditStore>();
+
         // The shared admin command set (create/revoke/rotate/list/init-db with audit) is not
         // auto-registered by AddZbApiKeyAuth; the gateway CLI and dashboard drive it, so register
         // it here over the already-wired stores, pepper provider and migrator.