unable to perform javascript while creating a layout in suitecrm 8.9

I created a custom module using Module Builder in SuiteCRM 8.9. After deploying the module, I am unable to execute JavaScript actions while working with the layout (specifically during record creation).

Additionally, I noticed that my module’s folder is not appearing inside the custom/ directory as expected. Instead, SuiteCRM 8.9 uses the extensions/defaultExt/ path for overrides, which is different from SuiteCRM 7.x.

I am sharing the directory hierarchy and the code snippets I used, so you can help me identify what I might be missing.