WHEN: developer needs to write or scaffold unit tests for a custom D365 object. Triggers: 'generate tests', 'unit test', 'SysTest', 'write test for', 'scénarios de test', 'test this class'. Generate X++ SysTest unit test code for a CUSTOM D365 F&O object based on functional test scenarios. [!] Only meaningful on custom/extension code (D365_CUSTOM_MODEL_PATH). SysTest tests in D365 are highly context-specific -- a generic template rarely compiles without adaptation. REQUIRED: provide test scenarios in the 'testScenarios' parameter (supplied by the functional consultant). Each scenario becomes a concrete test method with arrange/act/assert. For tables: generates tests for find(), exist(), validateWrite(), initValue(). For classes: generates stubs for each public method listed in scenarios. Uses REAL field names and method signatures from the knowledge base.