Fix: Empty default packages caused by models without event definitions

[zongqichen]

When models lack eventResources definitions, the ORD loader initializes empty packages due to overstrict conditional logic:

// lib/ord.js (Line 150)
if (
  _getAPIResources(linkedCsn, appConfig).length &&  // AND condition
  _getEventResources(linkedCsn, appConfig).length   // ← Problematic check
) {
  ordDocument.packages = _getPackages(...);
}

It will cause following issues:

• packagesIds is empty
• no partOfPackage in entityTypes

We need to investigate why do we need to consider eventResouces when get packages and extend fully tests. At the moment, ord test does not cover no event testcase.

[swennemers]

Please have 2 test cases:

1. with only api resource
2. with only event resource

to ensure having any package calculation is independent of other resource types being available.