Intaker and Web API integration

// OnMessageAxtionExportXlsx · current source excerpts
authorizationMapping = ExportAuthorizationResourceCatalog.GetMapping(
    importTemplateSheet.IntakeSheet);

var reader = new LegacySqlAuthorizationGrantAdapter(
    (System.Data.Common.DbConnection)kata.Db.Connection, msg.Header.Product);
IAuthorizationContextResolver resolver =
    new SmartExchangeAuthorizationContextResolver(reader);
var principal = await resolver.ResolveAsync(
    new(userId, msg.Header.Product, authorizationMapping.ResourceKind));

authorizationPlan = await exportAuthorizationClient.PlanResourcesAsync(new(
    requestId, principal,
    new AuthorizationResource { Kind = authorizationMapping.ResourceKind },
    "export"));

// After PrepareQueryForExport; before filters, paging and Execute:
exportQueryBuilder.ApplyAuthorizationPlan(
    authorizationPlan, authorizationMapping,
    new SqlKataAuthorizationQueryAdapter());

// resourceKind, action, policyVersion and rootIdColumn are server-owned.
// The database connection must match the authenticated product instance.
var reader = new LegacySqlAuthorizationGrantAdapter(connection, product);
var resolver = new SmartExchangeAuthorizationContextResolver(reader);
var principal = await resolver.ResolveAsync(
    new(userId, product, resourceKind), cancellationToken);
var plan = await policyClient.PlanResourcesAsync(new(
    requestId, principal,
    new AuthorizationResource { Kind = resourceKind, PolicyVersion = policyVersion },
    action), cancellationToken);
var mapping = AuthorizationSqlMappingFactory.Create(
    resourceKind, action,
    new AuthorizationSqlAttribute(rootIdColumn, AuthorizationSqlValueType.Guid),
    SmartExchangeAuthorizationRelationshipRegistry.GetRelationships(resourceKind));
query = queryAdapter.Apply(query, plan, mapping);
// Then count/page/execute; never ignore an authorization failure.