feat(auth): Program.cs integration for Audit Logging (AEG-AUTH-001 Part 2)

- Register IAuthAuditSql (AuthAuditSql) in DI
- Add AuthAuditMiddleware to pipeline after authentication
- Fix AuthAuditSql using statement + NpgsqlInet construction
- Fix GetAuditLogsEndpoint response mapping (AuthAuditLogEntry → AuditLogItem)
- Build verified (Release mode, 0 errors)

Implements audit trail for all /api/auth/* endpoints:
- Captures event type, status, IP, user agent, endpoint, error details
- Immutable append-only storage with compliance views
- Async non-blocking logging with graceful failure handling
- Ready for 0047 migration application and testing

WBS: AEG-X-005 (JWT/OIDC/fail-closed) + AEG-AUTH-001 (Audit)
Gate: G3 (Shadow Run API)
Status: CODE_COMPLETE → MIGRATION_READY

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

src/KArtSell.Host/Features/Audit/GetAuditLogsEndpoint.cs

@@ -47,13 +47,29 @@ public sealed class GetAuditLogsEndpoint : Endpoint<GetAuditLogsRequest, GetAudi
             ct: ct
         );
 
+        var items = logs.Select(entry => new AuditLogItem
+        {
+            AuditId = entry.AuditId,
+            EventType = entry.EventType,
+            IdentityId = entry.IdentityId,
+            Username = entry.Username,
+            Role = entry.Role,
+            IpAddress = entry.IpAddress,
+            Endpoint = entry.Endpoint,
+            HttpMethod = entry.HttpMethod,
+            Status = entry.Status,
+            ErrorCode = entry.ErrorCode,
+            ErrorMessage = entry.ErrorMessage,
+            OccurredAt = entry.OccurredAt
+        }).ToList();
+
         await Send.OkAsync(new GetAuditLogsResponse
         {
-            Items = logs.ToList(),
+            Items = items,
             Total = total,
             Page = req.Page,
             PageSize = req.PageSize
-        }, 200, ct);
+        }, ct);
     }
 }